And a party needs no constitution masters at all. Your argument here is Intelligence is not important because you only have a few Intelligence skills, but then you have no constitution skills at all. If you need 1 or 2 loremaster that is 20-40% of the average party and unless you have a Wizard or Artificer it is not a given you are going to have that.
Constitution checks are less common than intelligence checks and Constitution, like Intelligence, is almost never vital to survival.
I agree.
My point is that the way D&D as a game is set up, having more than 2 PCs with positive Intelligence scores above 13 is
always* overkill and purely detrimental*. In D&D, you never* roll enough vital INT checks to warranted needing more than 2 PCs rolling for it. And rarely are you allowed to do so for important checks. For minor story checks and puzzles, everyone gets to roll and the 8 INT PC can attempt to just roll high.
Whereas having more than 2 PCs with positive Intelligence scores above 13 is
merely suboptimal. CON has a non-skill benefit that benefits every PCs. And at hack and style tables that benefit comes up often.
*unless you are playing a mystery heavy campaign.
Then you get to Saving throws and BOY is INT saves nea useless if you aren't facing psionics. DMs tend to have to homebrew just to make INT saves matter.
Where CON is a big three for saves.
Dexterity yes, Constitution no. Unless you play a class or race that has abilities that use Constitution it is not very useful at all.
I have played a number of 1-20 point buy characters, form a variety of races and classes and never had much use for a Constitution above 12 at all.
Wisdom is more universally useful than Constitution. and unlike Constitution, Wisdom is often vital for survival both for perception and for Wisdom saving throws.
CON is a big three saving throw and add a bit of HP. It's s beneficial to all.
INT is the least or second to least appearing saving throw and has no combat benefit for any PC who doesn't have a class feature based on it. And INT checks are low threat checks based on identification which low INT idiot PC tend to get to roll. INT checks are rarely hurried where only 1 PC gets to attempt it.
*unless you are playing a mystery heavy campaign.
Loremaster is a low priority party role.
INTELLIGENCE should be an option for Light and medium armor AC like in 4E to make it matter to every PC.