I agree with you, except that for some people who apparently have enough pull to get their views put in the New York Times, defund the police means precisely disband, or abolish, the police.
https://www.nytimes.com/2020/06/12/opinion/sunday/floyd-abolish-defund-police.html
So, if the goal is understanding, when someone says "defund the police", it's helpful to ask what, exactly, does that person mean by that phrase. Because quite clearly for at least some fairly influential people in that movement, defund the police means abolishing it.
The term "defund the police" is problematic for another, related, reason: whenever else the term is used, it usually means "abolish". When policians talk about defunding planned parenthood, they generally mean take all federal funding away. And it is understood that if federal funding goes away, it cannot sustain itself, and thus will disappear. So defunding here has the goal of eliminating. Same idea if we are talking about defunding the department of education. When that is proposed, it usually means abolish. So the term itself almost invites confusion, which is why it's best to ask what a person means when they use it. Similarly, it's best if someone uses it to also give a little clarity as to what they mean.
If, of course, the goal is understanding, or to be understood. If the goal is just to shout or react to slogans without caring whether there's real understanding, well, that's different.