Whether or not it’s a good change is likely mostly subjective. I’m guessing Discord made the switch to be more in line with other mainstream social media platforms, and to reduce confusion.
Personally, I kind of like the old way more. It means there could be 10000 different people with basically the same name. Other than paying for a specific number, there is no issue with a person grabbing a handle and then it not being available to anyone else. Otherwise, eventually, a lot of handles will be used up, maybe even dead, so people have to come up with increasingly creative ways to get a unique handle – or just settle on adding some numbers to the end.
I’d even go a step further myself and remove handles completely. Just use a random unique identifier, like a hash or GUID for the user – which a lot of platforms do under the hood anyway, since you can change your handle in many of them – and use invite codes, QR codes or similar to add friends. We don’t need this username / handle rotting that just gets worse over time.
It’s still refreshing to see how many subreddits ended up joining the blackout. Over 8000 joined, including some big ones, and (as of posting) 6800 are still either private or restricted.