There was a whole generation of touch focused devices around '99-'03 or so, mostly hampered by too slow hardware, too low resolutions, cost, awful battery life and awful capacitative touch.

I worked on a Linux based tablet back in '99, that had all of those flaws.

Apples biggest innovation was recognising when the hardware had caught up enough to make this attractive to normal consumers.

That's not a small thing - the entire rest of the industry tried,failed, and wrongly assumed the failure meant the concept was a dead end and mostly abandoned it, before Apple resurrected it.