I could be wrong but "defund the police" was just a discussion point for activists talking amongst themselves. In that context it makes sense. What happened was that this inelegant phrase was seized as a weapon by the right and then every Dem politician had to answer if they supported the idea of abolishing the police.

I'd imagine that many people would be receptive to the idea of taking some money out of police budgets so social workers and people trained in deescalation can be hired. For example cops aren't a good fit when dealing with people facing mental health crises because they mostly turn to use of force and make a bad situation worse.

If you twist this into, "are you in favor of abolishing all police?" then most people are going to say, "hell no, what a stupid idea, you moron".

Now any discussion about the rotten state of policing in the US had been effectively hobbled. Discussion is shut down. The right wing wins.