The CEO made a remark about Trump, and used his corporate account for it.

If I recall correctly (no press statement was made by Proton), it was a personal remark on a corporate account, which he was quick to allow anyone to do. It also didn't support Trump as a whole, just a remark Orangeman made about getting small business a level playing field (which I totally trust from an olicharch).

I'm still sticking with Proton for the foreseeable future, as its privacy awareness and advocacy is still a core business value.