Yes this was a dick move, but I think the worst thing you could've done was then moved in front of them again. It was clear you weren't keeping up with the pace of traffic, and doing this would have only aggravated them further. All it takes is for them to put their foot down and knock you off. The best thing when on 2 wheels is being as defensive as possible.
Young guy/woman (hard to tell !) driving very aggressively through queuing traffic in Manchester city centre. Getting beeped at constantly. Will undoubtedly cause an accident soon.
I'd have squeezed in the gap
Let them get in the passenger side