Why do people ask "Is this still available?" on marketplace/sale sites & then after a prompt response 'yes' it's 🦗 crickets? What's the scam?

No idea. That whole thing is bizarre. Some will set up a whole plan to meet and then not answer when is is time to meet.

Or wait days to respond so you spend 3 days on one item just waiting on the responses. I started blocking people when they didn't respond. And i always check profile before responding because many of them are fake scammers who dont even live nearby when the post is clearly marked no shipping.

Someone went through this selling an old car. It was up on marketplace with a price, and they would get stuff like, is it still available? But then you'd never hear back from them.

For FB marketplace there's this button if you're a buyer and you're just browsing:
I'm wondering if people are pushing the button without meaning to.

I honestly think most of them are accidentally pressing the button.

I hate everything about Facebook marketplace. I wish it would just go away and we could look through the penny saver and classified listings again. It was better in every single way