They’ve finally started doing a better job of not requiring you to pickup your luggage while transiting only to drop it off another belt a minute later.
But that’s not universal.
If you don’t require transit visas it becomes fairly trivial to get into the US and claim asylum while supposedly in transit to somewhere else.
https://www.alllaw.com/articles/nolo/us-immigration/can-you-...
The only trick would be if the government a priori refused transit visas to people suspected of seeking asylum without hearing the asylum case, which would be a gross violation of immigration law.
How could it?
I think you may be thinking of refusing to honor an existing valid visa at the border, rather than refusing to issue one at all before someone travels.
Only citizens have an absolute right to entry.