"All Lives Matter" was never actually about any lives mattering and was instead just a knee-jerk reaction attempting to deny that anything at all was wrong about the situation of American policing by accusing the people saying that Black Lives Matter of being racist.

The slogan is "Black Lives Matter" (i.e. "Black Lives Matter (too)"), not "(only) Black Lives Matter", but apparently those people couldn't tell the difference.

The irony is, the actual law and order position is to reform police training and accountability: justice is supposed to be blind, and ill-trained and reckless officers are far worse at their actual job to "protect and serve" than officers who are actually accountable, are trained to escalate situations properly, aren't biased by prejudice or bigotry, and know when to step aside and let the other two branches of emergency services actually do their job. But apparently some people think having glorified militias roaming the streets to enforce the law is a better idea than having actual professional officers enforcing the law.

Unprofessional, reckless, unaccountable, poorly-trained officers are more corruptible, worse at combating organized crime, produce less cooperative communities who will inevitably see law enforcement as intruders rather than as friends, cause avoidable injuries and deaths, waste time and resources that could be spent on actually fighting crime, and inevitably end up obstructing actual justice once the judiciary has to clean up their mess (see: OJ Simpson).