It's good for YC to do this and will benefit every startup in the long run. Google has been one of the sources of the AI boom, and provides liquidity by acquiring startups. But as YC argues they've monopolised distribution channels to the point where you need to go through the Google toll booth every time you want to access the market. This tax on founders to reach their audience makes many types of businesses unsustainable and impossible, especially for products where usage != sharing.
You mean kills potentially successful tech companies of the future by acquiring startups to cement their dominance.
I get why people on this site are in love with the idea of building an unsustainable, money-losing business where the only path to success is being acquired by a tech giant. It's like winning the lottery! But it helps nobody, it hurts your customers/users, and it hurts innovation. It's also stupid, as a successful tech company could potentially grow as big as the giants you're courting (ESPECIALLY now that the FTC has started finally doing its job). Why else do you think they're spending so much money to acquire you? It's easier on the ego to call it an "acquihire", but the truth is that they're just paying a maintenance tax on their monopoly.
Every time people complain about how detrimental big tech is to society, it ultimately comes down to this sad strategy.
Of course it is good for YC to do this. They have significant investments in OpenAI both directly and indirectly through the countless startups they've funded whose core is OpenAI.
And it's ridiculous to act like (a) you are forced to go through Google to access the 'market' and (b) that this is somehow unusual or untoward. They are an advertising company and not the only one.