With the passing of great modern architects like IM Pei and Kevin Roche, monumental architecture is becoming less relevant for today's society, says Aaron Betsky.

I heard a story a few years ago about the late IM Pei. Architect Sandi Pei, an old family friend, told me his father made a pilgrimage to Taliesin West, where I live and teach, to meet Frank Lloyd Wright.

After driving across the country, he pulled up to Wright's "winter encampment", only to have Mrs Wright's Irish wolfhounds jump all over his car, barking and snarling. He turned around and never met the master.

It seems a fitting image by which to remember IM Pei, somebody who respected tradition and sought to continue it in his own way, but who was modest in both how he did so and in his personality, and stayed away from confrontation.

If Wright exuded charisma and indulged in endless experimentation, and if younger architects each worked hard to create their own style while rebelling against their parents, Pei sought to make simple things that yet aspired to his version of architectural mastery.

Pei respected tradition and sought to continue it in his own way

There is more than the loss of an architect here. With Pei's death, the last of the modern monument makers has passed. One after the other, those masters (all male) who updated the notion of designing structures for important institutions, by devising a stripped-down mode, have died.

Pei outlived not only most of his peers but also most of the postmodern architects who brought a lighter and more irreverent touch to such a task.

Pei's best work was like that of Kevin Roche, whose death preceded Pei just a few months ago. It rethought the essence of the classical monument – big, imposing, hierarchical in its facade and plan, composed of materials like stone and elements like columns, that stood outside of the regular cycles of everyday life.

Instead, these architects reduced the monument to blocks that they cut, honed, sliced. It opened them up to the complexity of communities and sites outside of what the discipline's traditions knew how to accommodate.

In Pei's work, a pyramid became glass and was not, like the original, a tomb, but its opposite, an entrance for a mass public that made the goods stored in the surrounding monument accessible.

These architects reduced the monument to blocks that they cut, honed, sliced

John Russell Pope's temple to high art, the National Gallery of Art in Washington DC, received an addition made out of shards that jutted around an open courtyard offering multiple paths and views into galleries that are more flexible than the main building's jewel boxes.

Pei's ability to manipulate monuments worked to ennoble the everyday as well: apartment buildings he designed early in his career for the developer William Zeckendorff became solid grids. They stood as inhabited steles in the confusion of Manhattan.

The best of his later skyscrapers, such as the John Hancock Tower, whose lead designer was his longtime partner Harry Cobb, became a glass prism reflecting and drinking in the Boston that unfolded around its triangular shape.

If Pei's buildings were mostly urban, Kevin Roche's greatest contributions were in suburban settings. He was able to open the corporate office complex out there with atria and open plans, while making structures for companies such as Union Carbide into modern day equivalents of Palladian villas or temples blown up to a vast scale.

His small arts buildings, such as the School of Art for Wesleyan University in Connecticut, were as fragmented and yet as solid as Pei's, and just as effective. His Ford Foundation Building in New York hollowed out the grand institution and gave it a green heart.

Pei and Roche's work, as well as that of Aldo Rossi in Europe and Kenzo Tange in Japan, to name a few of their peers, all served as correctives to both the dissolution of the monument during the 1950s and 1960s and is ponderous preservation in New Brutalism.

Combining an awareness that we need certain focal points, anchors and community centres that are larger than life in both scale and design, with a realisation that we also want such buildings to open up to all us, regardless of our cultural backgrounds, our abilities, or our tastes, they used the twin strategies of abstraction and fragmentation to great effect.

What they did not do, however, was to create a school or have an effect in the discipline beyond their own work. In many ways, their work was the end of the line, ruins left in the jungle of late modernity. They did not teach, and not many people tried to imitate their designs. They also became unfashionable and, by the end of the millennium, much of their commissions had dried up.

Roche tried to fight back through unfortunate forays into postmodern allusions, but Pei retreated into the making of a few jewels of buildings, such as the small museum he designed for Suzhou, China. Each one was specific and impeccably detailed, delicate in scale and yet imposing in its effect.

Pei also outlived almost all of the next generation, who responded to such earnest efforts with whimsy, expressive form and even further fragmentation.

Most recently, we lost Stanley Tigerman, whose irreverence masked a dedication to the making of serious form, plan, and meaning in buildings that ranged from libraries for the blind to holocaust museums and memorials.

The notion of making monuments seems outdated

Pei even outlived Philip Johnson, the man who played court jester to his almost regal elegance.

What then, is the legacy of men such as Pei and Roche? Certainly the era of white men ruling over the profession should come to an end, even though it seems to be hanging on with a tenacity that is both surprising and disturbing. Certainly the notion of making monuments that are meant to last and appeal to all seems as outdated as "big tent" political parties or established religion.

The idea that we should have focal points for our culture, and that they should represent values that endure – and thus that their homes should be monuments – seems difficult to defend in a world of continual change, division and doubt.

Steven Holl, Tod Williams and Billie Tsien, Frank Gehry, Peter Zumthor and Arata Isozaki, to name just a few still active designers, are trying to keep that tradition alive. But their structures are riven apart, both literally and metaphorically, by the need to be open and pluralistic, by restricted budgets, and perhaps by their own self-doubt.

To stand in front or inside some of IM Pei's best buildings, whether the East Wing of the National Gallery, the New York University Faculty Housing, the National Center for Atmospheric Research outside of Boulder, or the Suzhou Museum, is to become nostalgic for the ability to make such masterful, and yet reserved architecture that accepts and shelters us all.

We can only hope that a new generation of architects will find a way to learn from such as IM Pei to make modern buildings that, even if they do not look or operate like monuments, are worthy of that name.

Photograph of Museum of Islamic Art, Doha by IM Pei is by Yueqi Jazzy Li.