Mail and calendar: i think mailbox and posteo should work well, they both support IMAP for mail and CalDAV for calendar, just get a nice client(surprisingly not many for calendar standard protocol. thunderbird on desktop and etar/fossify calendar on android. stock one on ios)
VPN: MullVAD is the best
Drive: Check filen, it’s cheaper and better, and has powerful CLI tools
Pass: Maybe unofficial self hosted version of bitwarden. It’s called vaultwarden, and don’t be afraid of selfhost, basically all you need to do is docker compose.
I don’t think proton drive is functional enough to replace onedrive… And you can self-host Vaultwarden so is it really a thing to ditch bitwarden? And most importantly Startpage’s result is “surprisingly accurate” because they crawl from google results. The author doesn’t even investigate to find this thing