FrogReaver
As long as i get to be the frog
If we're going to have classes, demarcating their boundaries is part of that. Sure, not every character of a certain class is going to have the exact same skills (even aside from backgrounds), but if classes are types (and there's at least an argument they are) then certain skills are, well, typical.
That sounds a lot like restriction for restrictions sake.
Someone earlier (I think) also said something about the limitations making it easier for beginning players to build a character, and there seems to be some wisdom there. Even that aside, some people find inspiration more in limitations than in ... the opposite. It's like a drummer choosing not to have any cymbals on their kit, or a music producer choosing to record on tape rather than a computer (differences in sound aside in the latter).
I don't fully disagree with this, but I disagree with the conclusion because it's a matter of degree. Choose 2 of 8 skills vs choose 2 of 18 is not really the kind of limitation that is really going to benefit a beginning player IMO.
Also, if certain skills go with certain classes, it serves a purpose similar to niche-protection, in that it gives all the classes something out-of-combat to be good at, or at least do (and I believe characters should have something to do in-combat and out-of-combat). I think is also makes the classes a little more coherent.
There's already too much overlap in skills and backgrounds and racial skills to really believe this kind of niche protection exists in 5e. If 5e had even greater restrictions on skills then this would be a viable reason to not remove the restriction IMO.
With the flexibility in backgrounds, you can make a character with at least one idiosyncratic skill easily enough; two if you go completely free-form. It's not so limiting that I at least feel straghitjacketed. Obviously, experiences differ.
I don't feel straightjacketed either. However, there's times when I can't take one of the skills I want to take on the character I want to make. I usually can find a substitute that still allows me to play some version of the character I had in mind, but I see no compelling reason that i should have to do that.