I don't mean the other should be disabled. Just that the amount zoomed with the tap should not have anything to do with the amount you've zoomed, or how much you can zoom, with pinching.
If you have pinched, of course you can tap to the next zoom or back to original if you are maxed. Or if you've tapped, sure you can continue by pinching.

I don't understand why the amounts are connected.

All I want is that the maximum amount zoomed by pinching is removed.