I'm a active Protonmail subscriber too, who downgraded to the mail business plan, because I too want Proton to focus on their core business and not engage in becoming a clone of Microsoft 365.
There used to be a regular vote on what users are mainly interested in. Maybe I missed it, but I too think that the risk of engaging in too many ventures will be the ultimate downfall. One last argument is, that hosting files and text and whatever is planned in the future weakens the legal ground to protect user privacy, as the (legal and technical) attack surface of hosting services is greater than just end-to-end encrypted email.
That said, I think privacy oriented people are desperate for exactly what you said you don’t want - a Microsoft 365 equivalent that is privacy oriented. I’d be willing to pay for it personally, and don’t think it automatically follows that launching a new product makes existing ones worse. Maybe they’ll get a lot more users that purchase the overall bundle and help them fund all these ventures better than ever before.
You can also check out our feature request platform and change the category to planned or completed to see recent activity https://protonmail.uservoice.com
Your comments so far read as detached and impersonal, especially with the more than conspicuous usage of plural pronouns.
So I really hope you listen to us, the subscribers, and try to keep focus on improving the products that you have already launched and that we are paying for, before getting distracted on other projects.
Honestly the basic features that are still missing from Calendar are becoming a bit embarrassing. It's also embarrassing for me with my business clients when my calendar system is the only one that doesn't seem to function like a normal calendar does - and they see that too.
You've done an amazing job with product development so far - especially Email - but please don't squander that. Some of your products really really need basic missing features and bugs sorted - and quickly, because you've already sold them to customers. I get the sense that your customers are unusually loyal (which is to your credit) but goodwill won't last forever.