Is this why when I'm on Etsy, some obscure, niche item that I'm looking at will always say "13 people have this in their carts right now"? Etsy doesn't seem like the type to me, or maybe that code is just flawed

I’ve been suspicious of Etsy for years for this very reason. Either Etsy is scamming or the sellers are playing games.

You can test it yourself:

Become an Etsy seller and sell something what wouldn't be even show up in search

Observe if "N people have this in their carts right now" shows up

...

PROFIT

I think they just include abandoned shopping carts in this number

...and those abandoned shopping carts are from Google Search Bot which checked the product prices...

Wait, how does this work? Google bots this complex, or Etsy especially made it possible for Google bot? Also Etsy shows price directly on page, so whats the reason?

For a while on change.org (2021 was when I observed it) if you were looking at a petition with n signatures, they would show you n-10 or so, and increment the counter erratically over the next couple minutes to add the remaining 10... as though people were rapidly trickling in to sign this very hot petition right this minute.

Yeah i never knew but figured their is no other reason to do this than to make you feel pressured to buy