People will suggest running your own mail server, and if you have the time and energy then definitely do that. But the next best thing you can do is simply just use your own domain. That way, you can at least decide to migrate your email elsewhere. Don't use the free domains you get from things like gmail or other providers, because then you have to _change_ your email address, and not just your MX records.
Good luck getting the same quality of service as gmail with your own mail server. The fact that gmail fails every so often (extremely rarely actually) is a good sign: zero failure would mean that they are over-investing in quality and losing flexibility. Gmail only needs to be as good as the best web service out there.
and the weight of google as well!
an individual mail getting onto an blacklist is most often than not a dead sentence for the address, the domain and sometimes even the ip.
but if google is at fault and email get into a permanently removed bucket, like in this event, it's in the interest of the other to play nice and accommodate for the fault.
I think people severely underestimate how hard it actually is to consistently deliver email in 2020 between dkim, spf and domain keys while tiptoeing around everyone else ip/email antispam services.