The left have trouble in this country adopting the 'defund the police' slogan because the Coalition government under David Cameron did just that ten years ago, and the left have been banging on about it ever since (as a part of their wider opposition to the spending cuts of the Cameron era). Whenever the subject of law and order, and any increases in crime, comes up, it is always mentioned as a cause. It is not really a cause of any crime and disorder, because although the numbers of police did reduce slightly, the number of serving police is still historically a high number:
There are also a raft of responsibilities that the police used to have that they have off-loaded onto other organizations and support staff (community support officers, office workers, councils, private enforcement and security firms, and the Crown Prosecution Service) that they used to be responsible for (like parking enforcement, prisoner transport, and prosecutions), and so the effective number of police available for dealing with the crimes that they have supposedly organized themselves to focus on is very high.
But anyway, since 2010, the left have argued for a restoration of police funding and staffing to pre-2010 levels. I rather hope they get their wish, if only for it to be demonstrated that the issue of police funding is a red herring and is not tied to the level of crime and disorder. Rather, it is that the police do not believe in policing and the judiciary does not punish wrongdoing.
The police were captured by the left many years ago, and have been working toward leftist aims ever since, having abandoned their primary mission of preventing crime, being mainly reactive in nature, but even still in many cases do not even bother to intercede during the commission of crimes or to apprehend wrongdoers. The police act most enthusiastically to enforce the left wing speech codes that are in force in this country, and prefer to patrol Twitter, rather than 'the beat'. They also react strongly to any perceived challenge to their authority, such as against someone who uses force to defend themselves from harm by others.