I wasn’t going to do it, but the reverential silence as 400 architects stood up for the Prince of Wales was too tempting. Just as the prince was leaving the lecture hall at the Royal Institute of British Architects after his speech to mark its 175th anniversary, a raging gut instinct kicked in, and I belted out, “Abolish the monarchy!”

“Absolutely not,” responded a plummy voice from somewhere in the audience. There were a few urgent cries of, “She’s the one in red!” The RIBA head of security was soon by my side, in a fluster, ticking me off for bad behaviour. It felt like being back at school.

Indeed, the editor of the Architects’ Journal patronisingly described me as a “naughty girl” in his diary column. Worse still, he implied I’d done it just to get publicity for my magazine, Blueprint. Is it inconceivable that I might actually want to see the monarchy abolished? People are such conformists these days.

There was another reason I felt compelled to heckle the prince. Architects have failed so miserably to tackle his reactionary ideas about architecture. Twenty-five years ago he started a style war, famously describing the proposed extension to the National Gallery as a “monstrous carbuncle on the face of a much-loved friend”. The impact of the speech was huge: the firm that had designed the “carbuncle” nearly went out of business, the National Gallery competition was relaunched and a postmodern design with a neoclassical façade was chosen.

The battle between modernists and postmodernists raged for several years. The prince made a TV programme and an exhibition about his architectural preferences, A Vision of Britain. He even built a village, Poundbury in Dorset, to demonstrate his “new urbanism” principles. But nowadays, many of his ideas overlap with those of the architectural profession, emphasising sustainability, contextuality and low energy design to tackle climate change.

So there was a sense of real shock when, in early April, the prince intervened again in another controversial London plan, the redevelopment of Chelsea Barracks, owned by Qatari royalty. Richard Rogers’ practice was proposing a modern design on a historic site: the prince wrote to the emir of Qatar asking him to drop the plans in favour of a neoclassical scheme by his favourite architect, Quinlan Terry.

It was with bated breath last week that the profession sat down to hear what new insult Charles would hurl at RIBA’s celebrations. But times have changed. The prince stressed the common ground he shares with architects and attempted a reconciliation.

Critics noted the prince’s attack on modernism. But the fact is that most architects agreed with everything he said. In his opening remarks, RIBA president Sunand Prasad even mentioned postwar “car-bungles” (housing estates that encourage car use).

Prince Charles’ ideas are as small-minded and anti-progressive as ever. It’s architects who have changed. Twenty-five years ago they might have challenged his parochial philosophy. Now all they can do is agree that architecture should embrace limits and designers should be less ambitious. The new conformist architect is even shocked to hear the view that having an unelected head of state is outdated and anti-democratic.

Vicky Richardson is editor of Blueprint