True, it may take a while.
Then again, Roberts was appointed while still relatively young, and likely to have two or three decades of potential time on the bench ahead of him.
Since then, Sotomayor was also relatively young when appointed.
I think this will become the new norm; if so, appointments are likely to have longer term effects. Still, Justices tend to try to remain on the bench until it is likely they will be replaced by somebody with a similar view of how things should work.