The problem is that character development is greatly simplified in the case of 5e.
For characters on level one, the difference between a character with proficiency and the +3 modifier is only a 25% chance of success more than a character without any bonuses.
Due to the lvl cap, it is unlikely that we will be able to achieve a proficiency bonus greater than +4 before the end of the game.
This is a low bonus, and it's no wonder that a lot of people feel like character building doesn't really matter.
In most games, the difference between an untrained character and one that specializes in some field is much greater.
I like how in 3.x some skills require training to be possible at all. I think the simple Barbarian "deciphering a magic circle" or "remembering something from foreign History he has never studied" fall into that category. This measly +2 from being Proficient in a skill is like the polar opposite of that.
