In the past many remappers have claimed their maps aren't detectable by dealers. We all know that if they look hard enough they'll be able to tell but generally dealers didn't have the tools. It seems that's changing. These docs are from the US and suggest that modified cars will be flagged on the database. It doesn't seem like they're voiding any warranty (well they're not allowed to anyway) but if there's a power train issue then it seems to remove the "mod friendly" dealers from sneeking it in under warranty. That was always a dubious practise as effectively some "mod friendly" dealers/franchises were effectively defrauding Audi.
Audi documents :
Another thought is that insurers will be able to more easily identify cars that are modded and not declared to them effectively giving them an argument not to pay out.