More ideally, the interview process would have found that OP was a better fit for the company and that the rewrite-everything guy was producing abnormal interview reviews and should be demoted.
You're absolutely right. Unfortunately the broken-ness of the interview process is not limited to the interview itself.
I've interviewed around 40-50 folks for $role at $wildly_successful_megacorp.
My qualifications: zero training, zero oversight.
I'm getting a lot better and more consistent. But I have still left a lot of interviews thinking how poorly I have done, and needing to reflect on how things could have gone differently.
It's very easy to think of interviewing folks as a chore or merely a favor to $other_manager. For something so vital to the long term health of the company, it's really appalling how little effort is put into it.
I think it's because anyone qualified to interview is probably qualified to do valuable work.
And so companies turn that around and say "Let's take our best and brightest, and have them interview candidates! Then we'll select the best candidates!"
But it's the same research / teaching faculty problem, where one skillset does not imply the other.
There is no such thing as a 'toxic person'. There are people who do not fit in a team, there are people who don't fit a companies goals, there are people you can't stand.
The most difficult lesson I've learned is even the worst person in the world has their uses and I only hurt myself by not admitting that.
If I can't stand a team I move on as quickly and professionally as possible because life is too short to fight pointless battles.
Sounds like the interview process worked for you. You found out that you don't want to work with him and didn't.