The only reason they released a year earlier than their native app SDK was to get their product out in front of competition that they knew was coming so they could claim they were "first".
Who was coming? What competition?
They weren't in a race with anyone to release the iPhone. Nobody was even close to what they had with iPhone at the time.
Android didn't start at Google. Google bought them in 2005, three years before the iPhone was released.
https://www.androidpolice.com/2020/05/24/android-was-born-on...
The exact UI doesn't matter anyway. Apple knew they had something and they knew Google had resources to compete. Don't forget that these companies compete over hiring talent as well.
Apple never, ever planned on only web apps and there's no evidence of that.
The first third party native apps were people who managed to get the gcc toolchain to emit a binary that the iPhone could run.
Then the App Store came out a few months later. Native apps caught on very well over just making html5 sites for iPhone users, because, in a lot of cities, AT&T's network just couldn't support all the users' very well. Even then, you were limited to a max of something like 20 (?).