Dozens of designers and architects signed a scathing open letter protesting a San Diego museum’s expansion.

The Museum of Contemporary Art San Diego (MCASD) is in the midst of a $75 million expansion that would quadruple its exhibition space to 40,000 square feet and expand parking areas when it opens in the La Jolla neighborhood in the fall of 2020. But the sleek redesign also strips away from the building defining elements of a 1996 renovation by Venturi Scott Brown, a firm with a fervent following in the architecture world. If it goes through, the postmodern entryway will become an indoor gathering area and a pair of vine-wrapped fiberglass pergolas framing it will be removed (one of them already has been).

Now, dozens of prominent figures in the design world have signed an open letter decrying the the new expansion plans, which are spearheaded by Annabelle Selldorf, the architect who has dreamt up white cube spaces for mega-galleries Hauser & Wirth, David Zwirner, and Gagosian, and was tapped to helm the expansion of the Frick Collection in New York. “We recognize the museum’s need to expand, but we ask that it do so without irreparably damaging a cultural landmark and in the process severely weakening La Jolla’s beloved village center,” the letter reads. “Scott Brown and Venturi are widely recognized as among the 20th century’s most important architects, and this building remains a shining reminder of their enduring cultural contribution.”

The resistance is led by the 24-year-old Izzy Kornblatt, a graduate student in architecture at Harvard who studied the 1996 design by Venturi Scott Brown and was so taken aback by its dismantling that he called the firm’s principal, Denise Scott Brown, who is married to her work partner, Robert Venturi. Scott Brown told the San Diego Union Tribune that she was “shocked” to hear about the new plan when Kornblatt called, and described the new design as “threatening the museum and The Village.”

Among the 75 signatories on the letter are Robert A.M. Stern, the former dean of the Yale School of Architecture; Martino Stierli, the Philip Johnson Chief Curator of Architecture and Design at the Museum of Modern Art; and the architecture critic Paul Goldberger. The redesign has been approved by a number of development boards in San Diego and at this point will almost certainly proceed according to plan.