"Some activists want both things means they can't be distinct proposals" is like claiming the FSF and libertarians are the same group because there's a lot overlap.
The issue is that "defund" would actually work for the original activists' goals (abolishment), so I respect it even if I'm not sure what the world would be like after it.
I don't think it helps anyone else's goals though. So I think they're mistaken to take it up. Also, it's easy to fight against (because your opponents can point to the abolitionists) and it makes you look bad to normal people (most people in the US like the police, including minorities, who are actually more socially conservative than white people).
To stop misconduct a better message would be to define those people as "not the police" by, like, making it possible to fire them.
https://twitter.com/BlackVisionsMN/status/126614972305388339...
https://twitter.com/sunrisemvmt/status/1279148959139758080
It actually makes more sense this way, the confusion is when people who don't want to abolish the police still want to defund them.