I think this is being misinterpreted a little bit. This only blocks attacks that exactly equal the final number. So for their example, AC 14, and final total being 23, 15-22 still hits and 24+ still hits.
It’s an interesting magic item but ultimately it’s too much additional math and dice for a turn.
Yeah Pathfinder 2e is good. It’s more crunchy than 5e, but that also means there are rules for most situations that come up. I like the 3 action system, much better than the old, “main action, swift action, move action, move- equivalent action” thing the old version had going on.