Never yet had a flight that’s too hot, they’ve always been far too cold, necessitating a blanket and/or a pullover. Definitely a personal thing, in the same way that some people are happy with their houses at less than 70deg (21c).

Crew (I’m speaking on behalf of one here) don’t like it particularly warm and generally prefer it slightly cooler, especially when they are working and moving up and down the cabin.

It’s often a very personal thing, and (being polite) can sometimes be related to people’s weight - the (ahem) slightly larger person preferring it cooler than the ‘less’ larger.