I think the unfortunate reality is that some people are intolerant of others who are insufficiently supportive of certain causes, and the only way to deal with those people is not to deal with them. The subject of this thread seems to be one of those people.
I think the unfortunate reality is that this isn't about individual people expecting support for certain causes. What you're looking at is fundamentally a social phenomenon - a belief that's been spreading from person to person and community to community that every person in the social group must support the correct causes in the correct ways, that anyone who doesn't go along with this is actively going against the cause and must be shamed and shunned until they do. It's the social spread via peer pressure that gives this its power. This isn't a new thing, it's been spreading amongst the tech community and elsewhere for probably well over a decade at this point.
I agree that this type of toxic peer-pressure is spreading, and I have no idea what to do about it. It reminds me of what Louis Fischer and Arthur Koestler described in their respective essays in "The God That Failed".
It’ll crumble if you allow them to continue pushing the matter and imposing upon you, enforce your personal boundaries and if they continue intruding, probably HR time or at least sidebar with your manager. Good luck in your new job otherwise!