Much depends on the dealer.
I took a 2018 VW to a dealer early in the fall for its 10k/1-year service and I don't think they ever hooked it up. I do have a few mods to it, alhough they're not as extensive as what some people do. But one of them might be considered more objectionable (start/stop is disabled). Dealer didn't say a word. In fact, I'm not terribly confident the ever even connected their scan tool to that car; it came back to me with just as many fault codes as it had when I gave it to them. (FWIW, I've never cleared faults in it either; they're useful for software testing, and many of them pre-date me taking delivery of the vehicle the year prior).
Anyway, unless you've got specific deficiencies you want the dealer to address, or there are explicit recall or campaign actions, the 10k/1-year service is basically "Change the oil, check the fluids and the tire pressure, and send the customer on his way." Personally, I wouldn't worry about it, nor would (or did) I revert any mods.