Yeah, but as you're "going mad" at Facebook, you keep engaging with the site.

You try to peer through the noisy results to see if any of them are actually a match, you try again with different terms, you give up and engage with a result outside your parameters, or (best of all) you give up and engage with an ad or get distracted by some other Facebook feature.

As far as they're concerned, engagement is the key factor and satisfaction is only a tiny little bonus when things work out. Engagement is what earns them money and makes them make bigger claims in investment statements and is what keeps eyeballs away from their competitors.

Everything is working perfectly for them... just not for you, and they don't really care. That was the big business insight of the 2010's and there's still very little reason for anyone in online media to stop aiming for it.