Interesting comment on Hubble grade from Will Bosi on the other channel. Seems like a blatant 9a judging by these comparisons :
I would to comment on why I believe Hubble is 9a. In comparison to the other routes I have tried/done around this grade there is no doubt it is one of the hardest. I consider Hubble to be more of my style of climb and it took me almost the same amount of time to do as Rainshadow(Meant to be hard 9a). Last year I climbed 2 former 9as out in Spain, the first being Jungle Speed in only 4 attempts(this is a climb Daniel Woods has just sent and regraded at 9a). The second route was A-murete which took two days and is still debated between 8c+/9a, I took 8c+ as Rainshadow and Hubble still felt significantly harder. More locally Evolution 8c+ felt over a full grade easier, which I also sent last year in only three attempts.
I believe even Ben Moon now takes 9a for Hubble and Adam Ondra has said "I believe that it isn't by any means easier than Action Directe, the world's first 9a established a year later"