How to Delete Your Facebook, Twitter, Instagram, and TikTok
wired.com
wired.com
From what I understand, self hosting is not really possible anymore if you want to ensure people get your emails. My wife is on an email server self-hosted with friends and it's hit or miss whether her emails go through because gmail and others will treat them as spam by default. Additionally, I believe security is an arms race that's now very difficult to participate in while self hosting.
On the other hand, there are lots or gmail alternatives, including privacy focused ones (or at least not data harvesting focused ones). Protonmail, tutanota et al
I have email as part of office365 which all in is about $15 per month (including office and storage). Not privacy focused in the least, but it's an industry standard of sorts where at least I'm not blatantly the product.