And here we are again. A confrontational motorbike rider who wants drama to post on YouTube. You overtook when there was no real room, you are impatient. You followed him and stopped alongside him. I thought you were going to pull a knife on him. Sometimes you just need to let it go.
Car driver doesn't have a clue. It's dangerous for motorcycles to indicate when filtering as it could lead drivers to believe they're taking a turning. This is why riders are trained not to do this. The same as car drivers are trained not to indicate when passing a stationary vehicle, like a bus stopped at a bus stop, for example.
I'd say they brake checked you on account of your tail-gating.