Had the talk, no change

Sex may not so much be at the bottom of the list as, on a completely different list. If she wanted to have sex, sex would be on the list of priorities.

Have you ever asked your refusing wife when was the last time she had sex? Refusers might experience sex like a traumatic event, such that it always seems closer in the rear view mirror than it really is, or that the number of times remembered is more than the actual. For example, at the end of my second year of marriage my wife was in denial that there were still ten condoms in the box of twelve that we started the year with.

I think this is a defence mechanism in the brain of many refusers.
Somewhere in the middle of the "talks" I had with the then W she made a statement that nearly blew me away. She countered my attempt to schedule some intimacy that evening by saying "we just had sex". I had  been tracking frequency and type of sex so when we arrived home I showed her my calandar. It showed clearly that the last time we were intimate was over 2 months previously.

It's not "a denier". It is someone who, for reasons, doesn't want to have sex with you.
It needn't be a psychological problem on their end and likely isn't.
There are a gazillion people who for reasons (they don't know me, aren't attracted to me, dislike me, find something they know about me to be unattractive, don't like the circumstances in which they might have sex with me) don't want to have sex with me. It doesn't mean there is something wrong with them.

Similarly, there are people (including my ex-wife) who WERE attracted to me and DID want to have sex with me, but then later on changed their minds about their attraction.
I'm sure all of us can forage the corners of our prior or subsequent married lives and think of people where the attraction was lost.
Maybe it was when someone yelled at a waitress, or picked a nose, or did something that reminded us of someone we don't like - the mechanism isn't important. What IS important is that it happens all the time, and it doesn't always mean that something's wrong (even if it's a misunderstanding).

So if instead of medicalizing it or posing it as "the kind of person someone is", and looking strictly at the behavior, it's not too hard to understand why two consecutive days of sex occurrences in a drought of 5 months might be seen as "all the time". How much sex with someone who you don't want to have sex with feels like "a lot" of sex? How about "any sex at all" - as the number?

Yes, there is gaslighting going on - but it's not just directed at the unwillingly celibate. It's a lie to oneself. Far easier on BOTH sides to start with the idea that there's something wrong somehow, rather than the lack of sex being an accurate outcome from the actual sense of antipathy or absence of attraction to one's partner. The latter fact leads to an outcome that's likely divorce, and both sides see it, and both sides become dedicated to maintaining this fiction of a marriage.

For the averse partner, the marriage depends on kicking the can down the road and burying their sense of lust - because to explore it would mean cheating. If they don't even let themselves think about that (for the very same reasons you are concerned about preserving the relationship), then it may appear even to them as "not into sex".

For the unwillingly celibate partner, the marriage seems to depend on centering on the problem at hand - the lack of sex. And that person pretends that somehow their partner just forgot that they enjoyed sex or that you are mutually attracted, which you are no longer.

And so the fantasy of marriage continues, even though it ended years ago.

Going from age 31 to 46 without any sex - I’ve read some stories of women using sex as a weapon but that’s the saddest amount of time.

Friends have all said that if you need to get out, do it by age 50 so you have time to find a new compatible person

I wasn’t told that and missed The window of time

Take advantage of your youth and get out and find a real woman.