Under What metric do you apply that? What goals did they have for his program?
My understanding was the purpose of buying Joe Rogan was 2 fold, one of course is to bring in new users, but that was not the only goal (maybe not even the primary goal) the other goal was to get more of their current users to have more listen time on podcasts and less on Music, they pay far far far far less for podcasts (in many cases nothing) than they do for Music.
If they were able to shift the total listen time it could have more than paid for Rogan even with out new subscribers
The contract is up for renewal very soon so if they drop him we know he did not meet their objectives. Somehow I bet they renew