Races choice no longer is a part of character building but only a role play / cosmetic choice. It will reduce the uniqueness of races/sub-races and even make some of them totally useless...
Respectfully, I don't think that's true at all. As of now, picking a race for our class is trivial. Ability bonuses are an overwhelmingly strong factor and there is no racial feature that could even come close to compensating for not having at least a +1 to Intelligence on a Wizard. To me that's not the trait of a good character building system. When we get rid of racial bonuses, we'll have to look at the race's actual features. Some race-class combinations will end up on top, as they always do, but to tell the good options from the bad will require some degree of familiarity with the system and not just looking at a number.
It's true that some races or subraces may now become less attractive. Others may become more so. Combinations we wouldn't consider before become viable. I dare say if a race's usefulness hinges on having the correct number for a particular class, that race is poorly designed and the ability bonus was merely band-aid all along.
I don't want to come off as unhinged, so please read this as if I'm calm and collected and not prone to hyperbole.
But respectfully, the goldfish and the great white shark are not equal. And when you create a system where the goldfish can be just as much of an alpha predator that uses strength and toughness to eat everything else as great white sharks, it really isn't easy to see the racial difference between the goldfish and the great white as anything other than a largely cosmetic difference.
Haflings are small and nimble. There's no rhyme or reason to them having just as much strength potential as someone who is half Orc. Meanwhile, someone who is half Orc is many things but elegant of foot and slight of frame is generally not one of them. Having a half Orc be as elegant as an Elf is just weird.
Yes, this change does open up a lot of new ways of playing characters. It does so by making the race of your character much less important and much more of a style choice. There are still racial features that might be relevant, such as movement speed or darkvision. But mostly we're ending up in a world where a human and a grizzly bear are totally the same, it's just that they have different proficiencies. And that is absolutely ridiculous. A level 1 grizzly will pwn a level 20 human in hand to hand combat. It won't even be tired afterwards. Similarly, a level 20 goldfish monk can kung fu punch a level 1 great white shark peasant all day and the great white probably wouldn't notice.
Different people are different. Different species are different. And that's entirely as it should be, in my opinion. But this change forces everybody and everything into the same box. And I don't think I like that at all.
True, the hypothetical 15 cha dwarf sorc will never catch up, but catch up with what exactly? When did D&D become a competition like that? And why does it make any kind of sense that every species has to have exactly the same potential for every possible profession?