That was the signalling for readiness following Speedy Trial. I was running the first taproot client for BIP 8, LOT=True which would have forced the issue at the same block height taproot was activated.

Nodes set consensus rules, but it helps to have miners enforce as well as it demonstrates broader consensus. If miners didn't signal, or gamed signaling as was done during segwit, then more would have switched to UASF approach.