Probably because SOLO doing poorly has much more to do with a dull marketing campaign, poor release date and an uninteresting concept that’s best early reactions said “it’s fine but check your expectations at the door”. The fact that Disney has focused much more marketing on their tentpoles surrounding it than the movie itself, overshadowing their own blockbuster to highlight TI2 and IW.
It’s the first Star Wars movie where people didn’t even care about spoilers.
Prior to TLJ even releasing there were people saying “super hyped for TLJ, but really don’t care about Solo. I may skip it”
Maybe TLJ’s controversy didn’t help Solo, but it’s definitely not the main reason that movie bombed. The people boycotting Star Wars at most made up a few million at the BO.