but I also recognise that Linux is in no shape for a non tech literate person just to jump into.

I mean idk. Either you are on the high side of tech literacy and then Linux is easy and does everything you want and more, but even on the low side its pretty good. I imagine that if a chromebook is good for you then just a vanilla Ubuntu/Mint will do. There does seem to be a valley in between where Windows, thanks to its propritary 3rd party catalog, just cannot be replaced.