The key caveat being that iSH does x86 emulation to achieve this, but otherwise it seems to looks pretty darn nice. I have yet to try it but now that I've switched over to iOS I may just download it to compare usage vs Termux.
It’s pretty slow; usually somewhere between 10 and 100 times slower for most language runtimes. On newer devices this is less of a big deal, but only because they are ridiculously fast.
iSH is great, I have it on my iPad (my phone is a Pixel with Termux), but performance is atrocious due to the emulation.
Maybe it's better on the most recent Apple SoCs, but on my iPad mini just opening a small text file in vim takes a second or two (instant on Termux/any other CLI I've used in the last decade.
Rsync is so slow as to be useless - I think because it takes forever to calculate the diff.