I love Mame. But it was already dated by the 00s. And even more so now.
The show doesn't have name value. For theatre aficionados, sure, but not for enough of the general theatergoing public under 75, and certainly not for tourists. It would requires a star to both sell tickets and cover up the weak elements of the show. And Toni Collette is not a big enough one. Revivals are tougher than you think. This ain't summer stock.
These 7 shows are, to my knowledge, the only commercially-produced musical revivals that have recouped on Broadway in the past decade. 4.5/7 had a star, 4 won the Tony for Best Revival, at least 2 only barely recouped, and all have more modern relevance than MAME:
Sunday in the Park, Hello, Dolly!, The Color Purple, Hedwig and the Angry Inch, Les Miz, Pippin, How To Succeed.