Probably not long, some users already got A/B'ed into testing "sponsored results"
Frankly the example they posted seems like a fairly happy one, where the user is explicitly implying that they’re seeking a specific physical product to introduce to their life. We’ve all seen where those monetization incentives lead over time though.
But you’re right—not even so much as a tiny word “Ad” like Google does…
Basically, this means the answer is based on a main webpage.
It shows the cute Mastodon logo and all :D