The extension is direct from Mozilla. If I didn’t trust it to request literally any permission, I should just delete Firefox entirely because it could do just about anything without having to ask me.

I even distrust myself. I don't run everything as superuser / with admin rights whole day long just because it's me.

The point is you should use elevated privileges when you need them. Not because some use case which is currently irrelevant for you might need them.

You do know the reasoning behind the Least Privilege Principle, don't you?

It's not that developers are untrustworthy, it's that software have vulnerabilities, and they get exploited.

The permissions being requested are things that all native apps get by default. I’m not worried about trusted code getting permission to something I trusted a hundred other apps with previously.

Those other apps don't regularly download and execute arbitrary third-party code, though.