Is dumping a cheating husband about seeking validation while staying with him is about admitting you were a bad partner?

I think this is something that is a case by case answer, and to be more specific I don't think that the existence of one of these automatically means the other is true.

A man cheats because his needs weren't being met at home. The basis of your question assumes that the wife can meet those needs. This is sometimes just not true. So it is unfair to jump straight to "you're a bad partner" because the problem could be the thing said man needs is literally impossible for the wife to provide. Example: The guy could be gay.

But my question is: do women who leave high-valued men do so knowing at some level that they will receive long-term validation and praise and attention for what is traditionally a bad move for older women?

Traditionally leaving a high value man was a bad move for women because things were much less civilized in the past. Women were much more likely to be taken advantage of if they weren't attached to a man. If a wandering man finds a house and a farm and a widow, guess who can get a new house and farm at the small price of murdering a widow? Humans have made unbelievably vast strides in morality within just the last 100 years. So the likelihood of someone taking advantage of you in such a overt way just for being a woman is far less likely(atleast in a western country). What I'm saying is that it's no longer a bad move for a woman to divorce a man, in many cases it's actually a good move financially.

Proof of this ability for women to be more self sufficient in this day and age is the amount of women graduating with college degrees and getting work is very high in America.

As for staying with a cheating partner. In my culture, very RP, leaving a man (with whom you have children) for being a cheater is considered very childish and selfish.

Just gonna give you the benefit of the doubt and answer your questions anyway, but I think you're a troll personally.

leaving a man (with whom you have children) for being a cheater is considered very childish and selfish. Unless, he is overly disrespectful

I'm just going to say I know of no culture where cheating on your wife isn't considered overly disrespectful. I will admit I am pretty ignorant though.

if he humiliates you by cheating with very young women

I know of no man that thinks so selfishly of himself that'd he want to cheat on his partner, but then think "better go after women older than her as to not disrespect her or her family." Whatever culture this is, I gotta say the mental gymnastics are impressive.

or doing a poor job at being discrete

If you know your husband is cheating, then I'd argue that he is doing a poor job of being discrete. You do realize that this makes every scenario in your culture where a woman would leave a man not seem childish or selfish right?

Anyway I'd like to know more about this culture because it sounds so foreign to me that such a deep violation of trust can be considered ok, and having a negative reaction toward said violation can be deemed childish! That's pretty hard for me to wrap my head around.

EDIT: Called you a trolled, 5 seconds in your post history suggests otherwise. My bad. But my head still "can't even" in regards to the idea that women are automatically considered seeking validation for getting out of a toxic relationship.