Have you considered that the problem manager might be threatened by you?
I would expect that - in 7 years - you’ve matured in your role, even if you’re not into career development. It’s hard to know how we come off to others, but you sound pretty self-aware. Sometimes we grow opinions and a backbone that just are not palatable in the current role, meaning we’ve outgrown that particular pair of shoes. I don’t see pussy-footing around as sustainable either.
Regardless, I’d be job shopping, even a transfer within your own company maybe. You’re not going to advance in this role under this manager. And, like a business, if you’re not growing, you’re dying - you want to be learning *something*, right? 10 years is a long time to just petrify in place, while watching a poor relationship become worse.
The upcoming holidays are a great time to contact those old references, have a quick coffee with a pal from your current job (a reference need not be this manager - in fact, good recruiters/HR people should ask if your search is confidential, so as to not threaten your current employment.
If you’re he’ll-bent on staying, read that Classic by Dale Carnegie: How to Win Friends and Influence People. As you noticed, it takes more care and energy to say things with the objective of understanding the other person (vs spewing our own p.o.v.). It’s a useful skill. Not often practiced IMO, unless you have an exceptional boss.