It looks bad. Even if you're targeting lowest common denominator hardware, you can do a lot more with the general art direction to make it look more pleasing.

I think the idea is that they hope it one day becomes so popular/has such strong network effects that people feel they have to be on it irrespective of how it looks. Or how healthy it is to be on there. Or how tightly surveilled you are on the platform. Or how likely you are to become a victim of harassment or worse on there. Or how your data and attention is misused.