Still, the involvement of ticketmaster will scare off a lot of potential customers - that company is more toxic than saying "Brought to you by Comcast and Bank of America".
Taylor swift used ticketmaster and I'd say her eras tour was quite successful despite it. So I wouldn't blame that as the factor for the Sphere's success or failure even if I dislike the choice.
If Taylor Swift had required fans to register in person at a DMV in a series of three different appointments two weeks apart she still would have sold out - when the demand is that high it becomes a bad data point for comparison.
As someone who doesn't follow Taylor Swift at all, the two stories that filtered through to me were
* Lots of people were pissed at Ticketmaster
* The tour was a big success
It seems like it was a success despite ticketmaster.
You can't book an event of any decent size in the USA without it being a required Ticketmaster venue, so unfortunately if you want to see any reasonably popular artist or a show at a big venue they are your only option.
That's quite true aye - we really need an anti-trust lawsuit against them.