I use Fastmail - not too expensive, really good webmail client, has working shared calendar that isn't OWA, and isn't advertising scraping my e-mail. I would have liked a more private service, but back when I moved from self hosted to a service, that was about the best I could get that also had calendaring.
I also switched to Fastmail. iirc they are not the best privacy wise as they are based in Australia. They do however have a no-nonsense IMAP connection (unlike Protonmail) and they allow multiple custom domains without extra pay. The IMAP connection however is not available on the lowest tier.
So far I've not regretted the switch, and it also integrates nicely with 1Password masked mails.