I think it's still a shitty move and I feel deceived. I opted out of training and it's impossible to see for me (in any practical sense, sure it's somewhere in the ToS) that this simple question leads to my data being stored for 5 years and potentially read by human reviewers.

If I opted out, then don't ask me this deceiving question or make it very obvious that answering it has these consequences.

They could be A/B testing model tweaks, and use it as feedback that way. It feels dishonest to give paying customers an opt-out for training on their data and then sneak copies by asking for general feedback without a prominent disclaimer.