Is there evidence for this?
I'm pretty sure people already know how to think. And IIRC tests of critical thinking (not subject specific) to college seniors and freshmen there's not convincing evidence that college really does that much. https://opportunityamericaonline.org/wp-content/uploads/2017... - also 4 years of anything tends to make an 18-22 year old a bit older and wiser.
A meta argument - colleges are at least halfway competent at assessing critical thinking, and if they were good at improving critical thinking then you'd expect to hear from the unis that can prove they did a good job, and you'd get more than just a slogan. Playing League of Legends also has a bit of face validity to any claim that it improves teamwork, problem solving, decision making under pressure, etc.