Your assessment that ENTERPRISE made Vulcans too emotional is one which I happen to share. My feeling is that to get some of the good talent that they got to go through the hassle of wearing this nappy wig, of having rubber glued to their ears and all this, they were going to have be cut some slack. As in allowing these people to emote. It goes without saying that actors rely heavily on their facial expressions, body language and emotional range to realize live-action characters, almost all of the time. In a way I can understand, but ... I would rather have bad actors acting all unemotional and stoic as Vulcans, than have big names in the makeup playing as themselves. But that's just me ...
So you believe that the Vulcan characters showed too much emotion because the directors in the episodes in which they appeared were unable to control and direct their actors?
As has been pointed out numerous times, there were reasons the Vulcan characters showed too much emotion. Did you miss the scenes with "head" Surak and Archer, the importance of finding the Kir'shara, Syrran's talk with T'Pol and Archer in the cave, T'Les, T'Pau and the other separatists, the unsavory clandestine "relationship" of certain Vulcan High Council members with a certain hostile race? Did all this get by you? The showing of emotion by the 22nd century Vulcans was not an accident, nor was it a result of rogue actors being allowed to define their characters on screen.
I suggest carefully
re-watching the first half of season 4.