Yeah, they might not be aware as it's not something people would be actively reporting.I hope so. But I wonder if Nintendo is even aware of it as the glitch was found on the datamine. As you said, they send mail and gifts and I wouldn’t even notice that there is glitch as it is not noticiable as say, villagers having wrong items in their houses.
I do have some gripes with the data mining myself though.
For example, saying that villagers with lower friendships are more likely to move-out doesn't seem to be working in my case.
I have Zucker now with whom I have one of the highest friendships with a move-out bubble for 3 consecutive days while the villagers I actively started ignoring since the data mine about moving villagers out was released, not wanting to budge.
Strange.