Andy Yen's values are incompatible with Proton's mission. He advocates for poor security practices, supports fascists, and he verbally abuses his subordinates. As such, I can no longer in good conscience continue to financially support a company with such terrible leadership.
Unfortunately for me, my subscription just renewed last month on a multi year plan, but it does give me time to browse for and experiment with alternatives.
If you're able, I encourage you to do the same and cite Andy Yen as the driving factor for your decision. We can't let these tech bro fascists destroy what little semblance of privacy we have left.
Yes, with Möbius Sync. You'll have to copy the photos on the iPhone to a directory where Files can see them because of a security thing on Apple's side, then connect Möbius to the Linux desktop running syncthing, and point Möbius to the photos location in Files to make the share.