Pixel 3 ($800): 4GB of RAM, starts at 64GB of storage, and has a 2,915 mAh
Pixel 3 looks future ready to me.
[1] Apple, supposedly the gold standard for long term smart phone support, has already added last years iPhone 8 (2,675mAh) and iPhone X (2,716mAh) to its throttling list: https://www.macworld.com/article/3317689/apple-phone/iphone-...
Also, for someone who often does informal photo sessions for friends or strangers, being able to share links to groups or albums of photos is super convenient. They can download the full album as a .zip, too.
Pair this with the Pixel's excellent camera, and I don't even miss my mirrorless M4/3rds. The only thing I find myself consistently missing is a good telephoto. I know Moment makes a case and accompanying lenses, but I use the $40 Google case.
I had to stop using my 3rd gen iPad after official updates made it so slow it was a chore to use as more than an eReader. No option to install an older or 3rd party build. No way to repurpose it for much else at this point.
I look at it like an old "smart tv" versus an old PC. The PC can always get a lightweight Linux build or something else to make it useful. The tv gets what's on it, the end.