My previous car(a Mercedes) had a very very simple solution to this - you clicked on the lock button twice and it just disabled the keyless entry entirely until you pressed any other button.

>>the advantage of completely preventing relay attacks.

From my understanding ToF sensors are good enough now to completely prevent relay attacks, the added time for the relay just adds too much of a delay and it gets rejected. I believe the newest range rovers use that, they went from being extremely susceptible to relay attacks to relay attacks against them being impossible.