My biggest worry comes from the way Proton handles Standardnotes. To use that, you have to pay for a yearly subscription to even host your own server.

In the past, I have compared Bitwarden's model - favorably - against Standardnotes. It seems much fairer to charge users for convenience of a note/password storing service, and not the simple existence of an open-source app.

I did the same as you. I think I'm only 3 months into my bw sub.

My experience so far has been that it's painless to export import my data, so although I won't be thrilled if proton takes a cue from them and screws us, another move won't kill me.

I switched to KeePass months ago to avoid this endless cycle of SaaS products exploiting users. Treat the cause, not the symptom.