I'm happy that worked out for you, but the whole cryptography signature of Apple batteries that throttle your phone if you get the wrong one is VERY different from "just pop out the back and get your new battery in".
Also, your information is slightly out of date. It’s possible to do the replacement yourself if you want. Here’s an ifixit guide based on apples official repair guide - https://www.ifixit.com/Guide/iPhone+17+Battery+Replacement/1...
They are talking about this kind of battery replacement: https://www.ifixit.com/Guide/Fairphone+3+Battery+Replacement... . The "TV remote" battery replacement kind.