How so?
You need skilled, and quick hands to do both. O_o
It makes sence to me ... where is problem?
Easy.
The problem is that the Rogue class is supposed to have proficiency in Thieves Tools by definition. It does not, and neither does it get Sleight of Hand as a free proficiency (nor should it). The Rogue still gets the same four proficiency skills, and it is entirely possible to build a Rogue who does not have Sleight of Hand, and thus is missing a vital proficiency they're supposed to get as a class feature.
Thus, the Rogue is losing a class feature they are supposed to have for no good reason whatsoever.
***
I will say, though, that because the Ranger's Urban Tracker archtype lists proficiency with the Disguise Kit, it's possible that Tool Proficiency is simply not ready yet. However, once it is, Thieves Tools Proficiency needs to go back to its own separate thing, and be granted by the things which are supposed to grant it.
