So, if you have poor ability scores you should just forfeit your proficiency bonus? A player would rather have -2 to a check than 0?
How does one normally suck at a skill? Even if that's possible, the reason to take the skill would be to...drum roll... stop sucking at it.
A PC isn't going to "convince" me to use Persuasion. The character must have an intent that leads to a check - it's not the check determining what the course of action is.
This is harsh. WotC did its darndest to make a game that runs smoother than 3e. But I believe it used 3e designers to accomplish this (maybe not the best call). We should applaud their efforts, even if they failed.
I think this is saying, "because there's no Gather Information skill which would apply a proficiency bonus, gathering information is more difficult." Except the DM sets the difficulty, so why would the DM raise the difficulty upon discovering that the PC doesn't get a proficiency bonus?