well since I'm not sure how high the latency with the cable is I can only compare AirLink to Native Quest 2 latency, and that latency is extremely noticeable. the difference is very much there and very easy to feel.
not sure how high the latency is with cable, but I would assume when using the official cable that the altency is way lower than on AirLink
and this "you won't notice it" that everyone always tries to claim... that's simply bullshit. if you don't notice it, that's great, good for you. but many people are more sensitive to this than others. which is easy to demonstrate by the claims of people that had the audacity to claim Killzone 2 has normal input latency, or that Rise of the Tomb Raider on Xbox One had no noticeable input lag. these people exist and that's why I will never ever give a subjective claim about input latency any value, because people like that exist... like, they actually exist
but maybe the latency over the cable is just as bad, who knows. but one thing is for sure, it is very noticeable on AirLink, not gamebreakingly so, but noticeable compared to native Quest 2 latency
edit: found somewhat credible data, the Link Cable has about 45 to 48 ms of input lag, AirLink has about 60 ms, so that's not much worse, but definitely worse, and 10ms of additional lag is absolutely noticeable. and remember that this can be worse if your router is not right next to you as well. so in best case scenarios you will have about 10ms of additional lag, in a less optimal scenario this can go even higher