There is also no need to perpetuate the fear of running your own email. Decentralization of core internet services helps us all, not just the person doing it. So to anyone seriously interested and willing to learn, I highly recommend running your own email servers.
If you expect 100% delivery rate, you won't necessarily get that, no matter who is running your email infrastructure. At multiple companies, I've seen email end up in spam even though it is sent from gmail-hosted company account to gmail-hosted company account. So that's the bar you want to meet or beat and beating it is not hard.
From ~7 years experience now, I don't observe any problems with email delivery. I don't do anything special. I use postfix, it is well configured and everything works fine. I host several personal domains and a couple small business domains.
And by doing so I avoid giving google the power to cut me off from email because some arbitrary ML gone bad.