I wish they did this before I made this account ;w; I think its cool since I remember people art styles and such and If I forget who someone is I can just click there profile ad bam cool lookin' art! I if I had a subscription I'd change the name for my other account.
I want to change my name so badly (I was suuuuuuch a weeaboo when I made this account...DX), but I need a dumb premium membership...
I don't think it matters too much with the whole "people won't recognize you", because it tells your watchers that you changed your name. I've gotten two notifications about that already and I remember them.
I already changed accounts, but I have many reasons for doing so. Not just the username but it's to do with certain works and a new direction I wanted to take for my art.
I think it's good to change usernames only if you feel like there's a true need for you to market yourself under a different name while maintaining your old works. If you find that it's not really essential for you, then I think there's no reason why you should unless you really want to.