The tweet that seemed to be bootlicking Trump was worrying and troubling in my opinion as well. However, reading this deeper analysis alleviated at least some of my fears https://medium.com/@ovenplayer/does-proton-really-support-trump-a-deeper-analysis-and-surprising-findings-aed4fee4305e

Also the foundation model decisively limits the influence of the founder. There seems to be no other European email service that’s quite on par with Proton. Therefore I still think they are the top alternative.