[throwaway09223]

If people commonly sent a "yes" to acknowledge receipt of a message, then of course I would.

The problem here is that a thumbs up emoji doesn't mean yes. It can also mean "got it." When people send me huge documents I often send a thumbs up long before opening and reading the document.

[NikolaNovak]

Do you do that when they send a message "here's some documents", or would you send a thumb up if the message said "Attached is a proposal for the client, are you OK if we send it out?"

Like, surely, in that case you'd treat a thumb up as a dangerous message to send as an ACK? :-)

As well, do you follow your thumbs up eventually with something else? Because if I read it correctly, farmer had from March to November to follow-up on the thumbs up ... as well, there was previous precedent with that exact farmer, which makes it hard to argue "Oh, those previous times I meant thumbs up as acceptance of contract, but in this case I meant is as just an acknowledgment" :-/

[GloomyBoots]

Based on the article, it sounds like he didn’t use a thumbs up emoji to accept contracts in the previous instances.

A thumbs up is definitely a dangerous reply in the same way that OK is, but people use it that way anyway. And while it was dumb on his part to be unclear, it was also dumb on the buyer’s part to interpret such an unclear answer as an acceptance.

As to not answering, people forget to respond all the time.