Or the police and local council would look like they are supporting racism and insularity.

No. If a bunch of fascists decide to hijack a national flag, which means a lot to many people, you don't just roll over & let them. You stand up & reclaim it back

Yes but probably not by councils. I think if pro-immigrant and pro-Palestinian and pro-environment groups started to fly the English flag this would work. But who is going to be the first? And what would be the benefit?

The benefit is to normalise its use for its intended purpose, thereby reducing the association with the fascists.

How can it be racist? Our leaders, through media channels, would have to frame the messaging too - flying of flags outside every public institution is a symbol of unity and shared belonging to the country - representing inclusivity and pride. Not division or exclusion. The USA even has a flag code.

The English flag is now widely used to express racist views, and this genie cannot easily be put back into the bottle.