I have mixed feelings. I'm all for bands continuing as long as they can, and Anika is a more than capable drummer (I'm primarily a drummer, so I already knew who she was), but that's not really what it's about. Anyone, even Neil Peart, can be replaced musically. But it feels weird when someone whose personality was such a core part of the identity of a band passes, it's never going to be the same band anymore.
I felt the same way when Taylor Hawkins passed. There are plenty of drummers out there "good enough" to fill the role, but Dave Grohl had said for years that Taylor was like his brother, and if he was gone then the Foo Fighters would be finished. So when he kept going immediately with a new drummer it felt shitty to me.
Again, I'm not saying they should stop playing because they lost their drummer, but it just feels weird to continue being Rush and playing the same songs when such a big part of who the band was is gone.