My impression is that it's hard to find powerful specs alone on an Android tablet. That seemed counterintuitive to me

I'd think that the extra space would help

but I think what's going on is that everyone gets a smartphone, and they make that their primary mobile device. Then if they have the funds, they get a tablet, most-often for dedicated movie viewing. The market for that is pretty price-sensitive, so tablets don't generally cost as much as flagship smartphones. As a result, most tablets tend to have good speakers and a decent display, but unimpressive radios, compute capability, and most other things.