It's important to preserve modernist and brutalist architecture, so I can sort of see their point. I'm surprised there isn't another option in that specific case though (Can they not just add doors to the stairwell? Or do they oppose that too?)
Too much brutalist architecture is being covered in tacky "neo-classical" plaster facades.
Brutalism is an interesting architectural movement, but speaking as someone who lives in a city that has human-scale architecture, lots of trees and lots of eclectic housing, I understand Europeans who don’t want their cities dominated by remnants of the misanthropic planning regime that was imposed on them.
Half of our cities have buildings just like that. There is nothing special about them... just ugly socialist reinforced concrete buildings. I would understand if there were just a few left over, but there are large neighbourhoods just like that.
A lot of people thought that we should not preserve pre-war architecture, and that's why we now have a lot of modernist and brutalist architecture in its place.
I do agree that aesthetics and fitting into the neighborhood should come into the equation somewhere: the Barbican is probably worthy of preservation, some random shitty shoebox municipal library or housing estate probably isn't.
You don't need to preserve everything to remember history. If we never destroy old buildings, we'd have to abandon all our cities and find new places to build new cities, because we can't just keep living like it's the middle ages (or whatever time period you feel we need to preserve).
Too much brutalist architecture is being covered in tacky "neo-classical" plaster facades.