You're doomed to this issue with old phones in general.

Even un-modified you'll then be stuck with an old version of Android that doesn't support the latest versions of apps and the old versions of apps won't work properly.

It's really a shame because a lot of old phones work perfectly fine otherwise.

Generally Lineage is the latest. Unfortunately, there are other issues (such as the blobs that Lineage needs drifting out of date, and it's usually suggested that you'll should backup and then wipe to upgrade to the next major release, etc.)