I have had mechanical keyboards four different offices (1 cube, 3 open workspaces) and got very lucky with people either not minding or, at one company, a co-worker saying "that's music to my hears."

I've had a friend on the wrong floor at one company who had to switch to MX Browns with o-ring dampeners.

If a company banned me from using a mech keyboard entirely, I'd start looking for another job.