I have to agree with OP, this phrase specifically reveals it isn't a good take:

> sales [the best product] were entitled to in the first place

Unfortunately, this is not, and has never been, how it works. The best product is never entitled to sales. Marketing, which very much includes advertising, is a massive, massive factor in sales.

So advertising entitles you to sales?

Of course not. A terrible product may not sell well even if it has great ads, for instance.