I haven't seen much of an issue with the anti-reflective coating issues in the 2016+ models with our organization's Macs. While I saw a couple of 2016 models with the issue I have yet to see any 2017+ models with it. I have noticed when cleaning the display that sometimes what looks like the anti-reflective coating issue is just a smudge from the cleaning cloth which usually tends to be at the extreme edge of the screen. Wiping the spot clears the blemish.
Of course there may always be a random display that wasn't cleaned properly at the factory or the anti-reflective coating was not applied properly, but so far I think this is quite rare with the 2016+ models.
FYI, I still use the traditional LCD cleaner on our organization's Macs without any issues since many times user's love to touch the screens with messy fingers and this is the only way to remove the dirt.
If the spot doesn't clean up with a clean cloth, then you can provide product feedback to Apple here (Apple will not respond personally):
https://www.apple.com/feedback/
You can also check out your local consumer protection laws or contact Apple corporate.