What's the point with that quite lackluster story in Endwalker?

[Kyohei]

Emotions can be highly effective at drowning out logic and reason.

This is how I convince myself Venat's behaviour could be realistic and how the script came to be accepted despite inconsistencies. It's still not enjoyable, but at least this angle makes it a bit more bearable.
Hermes' unhealthy emotions lead to the situation first-hand. Venat wasn't more immune to being emotional imo, her bad course of actions might as well have stemmed from being overwhelmed.
It is something I could've agreed with. That she made mistakes and errors of judgement, for the situation was above what she could handle correctly. That her sight and reasoning got clouded by the loads of information to process, urgency of the situation, fear of doom etc...and she ultimately couldn't and didn't see other ways out than the one told by future WoL.
Like when someone removes a plate from the oven, realises it's burning hot but don't put down immediately because of the shocked state and latency to process signals even though there are other people screaming to put it down. When the logical process finally kicks in it's to late hands are burnt, only thing left is to heal it. In the span of seconds, a situation that could've been avoided if logic was the first process to kick becomes a long painful coping with no other ways. Sorry but it's the best example I've found on the spot.
All of this to say emotions (of all kind) can highjack thought processes, it does happen and no one's immune to it. It's plausible to think anyone even the most talented are prey to it.
Anyway of course the story doesn't depict her in this fashion but it could be a way to think about it.
This, coupled with how Yoshida was so proud to announce back then that the guideline of Endwalker was emotion...Could've totally fit better than the mvp omniscient omnipotent messiah theme around her, the total opposite of a flawed person.
Honestly when I heard that at the time I was sceptical for the very reason emotions often lead to illogical and unreasonable behaviours/situations, which I dislike. The prospect of having the arc's last expansion based on such a volatile subject wasn't reassuring to me but after ShB I held confidence the story would be great regardless of the core subject.
What a shame it turned out the way it did.