What happens if somebody doesn't play Int 5 in the manner you would choose? If you just move on with your life, you and I have no disagreement. If you get all judgy and your game experience is ruined, then you're that guy.
It would be handled in a more diplomatic manner than that which you are suggesting, between sessions, so as to cause minimum disruption - we would certainly not make a scene about it at the table. The old character would probably end up being written out of the game, and the player would roll a new one more befitting to their play style.
Thankfully all our DMs are proactive, rather than reactive, and get involved in the character creation process with the players, so that expectations are made clear beforehand from BOTH sides.
"OK, so you've rolled a 5, where are you going to put it?"
"I thought maybe Intelligence."
"OK, well before you do that, you should be aware that it will hamper your character's ability to interact with in game puzzles, planning etc. Plus a lot of the plot and interaction we have is driven by Arcana, History and Investigation, are you SURE you want to put it there?"
If the player agrees, then he will be expected to play in that manner.
If the player however replies along the lines of:
"No. Int saves aren't very common so that's the best place for me to dump it."
... then they are probably not a good fit for our group's play style.
This is a simplistic example, but it gives an idea of the general approach of the 4 guys who take turns to DM our groups. Session 0 is always - meet the DM for character creation, campaign background, and any system explanation which may be needed.