The hardest part of switching email providers is updating all the sites, apps, and services that have my old address. Everybody wants an email address these days, and they all manage it differently, so it's on me to figure out how to update each one.
Some are easy. Others are not! An alarming number use my email as my login and won't let me change it at all. Some of those further won't let me delete my account, so I guess they'll have my old address forever. Some sites, like Patreon and Steam, seem to support this, but when I used their update email form, it simply didn't work! I had to contact customer service.
It's a lot of tedious work, but realizing now how my identity was shared across a vast network of sites who don't handle that with respect, I'm reassured that it's worth the effort.
New rule of thumb: only actual people get my personal address. Everyone else gets a secondary address / alias that keeps different facets of my life separate.