Did you expect the controversy to result in less sales? I mean, as a casual pokemon fan, I didn't care one bit about the so called controversy, I'm sure nobody who isn't a super hardcore pokemon fan cared at all. And for any hardcore pokemon fans, do you really think any of them would refuse to get the game just because of that?? They're still gonna buy the game because they are hardcore fans, they're just also gonna complain about it online. The only thing that mattered was it was the first core pokemon game for a console and its on the super popular Switch, so yeah its gonna sell like crazy.
The only way I'd say it was held back by the controversy, though really I'd say it was less about controversy that your regular gamer doesn't care about and more about just how the game didn't really do anything groundbreaking for the franchise. And that is just that it hasn't gotten the amazing word of mouth as say BotW, Odyssey, AC:NH, and so on did because Sw/Sh is really just an okay game, nothing to go around telling everyone its a must buy.
After all of the controversy with the lack of content and corners cut, I expected SOME kind of negative reaction. Slightly lower sales, shorter legs, something. Instead not only it becomes a massively successful launch, it becomes the immediately crosses the 15 million mark that most Pokemon games need all of its lifetime to reach and it's going to end up becoming the second best seller in the franchise. This is sad because either the hardcore fans who said to boycott this bought it anyway, thus giving up on future games becoming better, or the casual base is so big it can more than compensate for the loss of the core base, thus making any kind of customer reaction powerless. Either way, GameFreak and The Pokemon Co. is just going to continue to degrade the series to sell more games faster and faster.
You know it deserves the GOTY.