Britney has been very vocal on Instagram of things that have irritated or agitated her (often relating to things she was forced to do or approve of, then deleting the caption after a while, but I usually catch them) and she has never mentioned the Broadway show let alone in a negative way.
As a big fan and supporter, while she ‘agreed’ and attended a workshop under the conservatorship, there is still the possibility that she enjoyed how her catalogue was being used (especially since they used Glory tracks) and is still fine with the production. She also released the song with Elton John but barely promoted or mentioned it, so it seems she has just been hands-off lately. The whole concept of the show feels right up her alley, so I can’t imagine she would be against it and not say something now.
I am big. It’s the REVIVALS that got small.