Roborock didn't win because of doing marketing, they won by being technically superior and word of mouth, in spite of lack of marketing, at least in the west.
Same how Japanese cars beat US made cars in the 1980s even though US cars had the most amount of advertising in the media. Even Steve Jobs said in the 90s that US brands have the best marketing and win all meaningless "awards by industry critics", but if you ask consumers which products are best, they all say the Japanese ones.
Chinese products are now the new Japanese. I still have no idea why westerners assumed "Chinese can't innovate, they can only replicate".