As a learning experience, sure, but most people are not prepared for what running a 24/7 mail service requires of them.
First of all, a static, non-residential IP is likely needed. The big players will flat out refuse receiption if your IP is registered as residential, so that rules out hosting it from your home despite having gigabit internet.
You also need SPF, DMARC and DKIM working, or major players will also flat out refuse reception.
On top of that, you need to implement the infrastructure to actually host a server 24/7, including patching and backups, as well as monitoring it for unauthorized access.
Despite all of the above, you may still find yourself on a spam/block list, and removing yourself from these can also turn into a large task.
Part of the irony of Gmail having outages is that Google and other "large players" have fought long and hard for a decade to make it harder to host your own mail server. It has been done in the name of fighting spam, but i doubt any of them minded it making it harder to run your own.
So yeah, build your own mail server as a learning experience. Then move the domain to someone dedicated to running it.
I purchased a lifetime subscription (limited promo offer) with mxroute.com. 10GB mail storage, unlimited domains and accounts (limited by space only), as well as a Nextcloud instance for all your users. Service and uptime has been nothing but exceptional. Customer support is actually reachable. The only downside is that the spam filter (SpamAssassin IIRC) is not as highly trained as the GMail one, so more spam comes through.