There is no such thing as an illegal protest. That is a concept made up by the people being protested against so that they can squash it. Protests are not supposed to be “convenient”. They are not supposed to be comfortable or nice or pretty. They are supposed to force people to face the issue and band together to bring about real change.
That’s not how it works. There is no country where protesting in the middle of the street without a permit is legal. There absolutely is something like illegal protesting, and what Just Stop Oil did was one example. Protests are about being seen, not causing inconvenience or even danger. You are not above the law just because you’re protesting. Getting a permit and demonstrating outside the white house would have been the correct way to go about this.
The only people who banded together as a result of this protest were angry drivers banding together to remove the nuisance, and climate deniers who got radicalized by the rage, seeing Just Stop Oil protests.
It’s one thing not to like illegal protests and a different one to equate them with anarchy. I understand that the term “anarchy” is often used as a synonym to “lawlessness” but in reality it is a movement that aims to eradicate societal hierarchies and replace them with horizontal organizational structures.
Also as I’m sure you know, law is not set in stone, it does change. Many things that are legal now, were illegal in the past. Sometimes in order to influence lawmakers we need to do illegal stuff, like non-violent disruptive protests.
If the protest isn’t illegal, you aren’t protesting, you are having a parade.