> IDK, maybe it's just the newer Android OS is such crap
I have a fairly new Pixel (so up to date OS) and none of these problems. Odds are it's something Motorola/Lenovo have messed up.
For better or worse, Android experience depends largely on the specific vendor.
I have a Lenovo tablet and it mercilessly kills background apps, no matter what you do.
I sprung for the extra version with 12Gb RAM as well, so it's just so pointless. It has double the RAM of my Android phone that doesn't do that at all.
So forget about syncthing or anything else you actually want to run all the time in the background. I need to remember to run it manually if I want things to actually be synced.
I could go through the rigmarole of installing a different firmware but it looks really complicated to do, and there are pros and cons of doing that too.