I thought I’d chime in and add that I’ve been using Zoho Mail for one of my domains for the last two years, and really like it - considering it’s free.
The web interface isn’t as nice as GMail/GSuite or Outlook, but I’ve been using it through Thunderbird and AquaMail on my Android phone and it works well. Zoho has a whole bunch of other interesting apps as well, all with a pretty generous free account.
I wouldn’t probably use this for my main or company email, for those I think paying for GSuite or Office 365 are worth it for some of the other tools, spam filtering, and how easy they are to use. But for my “side hustle” or smaller scale sites, I think Zoho is a worthwhile option that’s better than the free email accounts and tools that come with most shared hosting accounts or domain registrars.