I'm interested too. I currently use Obsidian syncing to my home server, but I like the idea of using Standard Notes synching to Proton Drive. Although you can't use Markdown with the free version of standard notes, so I'm hoping full featured Standard Notes will be included with Proton Unlimited
I'm in the same boat - can't wait to have a fully integrated alternative to Obsidian in my Proton suite. They are certainly working on a step by step integration, although in Proton speed. So maybe in a few years or so.
Still interested to see how this pans out. Started using Standardnotes after the announcement
Simplelogin joined Proton on April 8 2022 https://simplelogin.io/blog/simplelogin-join-proton/ July 29 that year the SSO login was implemented https://www.reddit.com/r/ProtonMail/comments/wb1byk/you_can_now_link_your_proton_and_simplelogin/
Proton acquired Stabdardnites on April 10 2024, so probably around July-August if it'll take a similar effort
I haven't heard anything.
When I did the survey, it was mentioned, but I have no idea how to access it