Some people do. There are options (like Proton) that offer good services that respect their users and their privacy and I personally like to support that

Proton!

The fuck if I’m gonna let Google train an AI off my emails.

Aye, as @forensic_potato said. And they have really good free options too, that are actually improved upon feature wise (only usage is limited)

Gonna pay once I can actually afford it.

You have to pay to get a real domain