It's crazy how much longer battery lasts after removing Google Services from Android.
Unfortunately for me, not only some of my apps require Google Services, but I also use a Samsung... I don't even have LineageOS available. Even if I did, custom ROMs on Samsung can't use VoLTE, which is a problem as they're shutting down 2G/3G where I live.

APK Mirror: https://www.apkmirror.com/uploads/?appcategory=nova-launcher
The Nova Launcher archive goes all the way back to 2012, so that's not a problem.
The thing is, if you install an old version and disable updates, you still depend on the Play Store not to update it. From time to time I manually open the Play Store to force updates, when some app isn't working as it should. So for me at least, it's only a matter of time until I forget about this and update the app.
We could block it from accessing the internet, but looking at DNS queries, this latest version also keeps retrying failed connections every few minutes. There's no way that's good for battery life.
In other words, while I'm sad and this is pain in the ass, it's time for me to move on.