Or indeed in one notable case the person who was arrested for a T-Shirt about "Plasticine action"
Whether or not the proscription was correct is irrelevant, the current law means that you commit the same offence showing support for IS or the Terrorgram Collective.
The police can’t simply ignore one proscribed group over another as that leads to all manner of weird and wacky outcomes.
It's not like these guys are the Taliban or the IRA, though some of them did chuck some paint on some planes.
So a person who is worried about Starmer's authoritarian tendencies lay responsibility for the police action at the door of number 10.
[0]: https://www.bbc.com/news/uk-england-merseyside-57403049
[1]: https://ukdefencejournal.org.uk/pro-palestine-activists-dama...