Usually it's a very bad sign when a company turns after the marked instead of being a leader. It's a sign of growing too big and getting conservative. It's a steady decline that is difficult to get out of.
Overwatch is a completely new franchise though, so in that regard its novel.
The cashing in can be seen in different ways. Selling out their Diablo IP to NetEase for a mobile game (and having the guts to market it for a PC crowd). Their microtransactions in WoW while still having the subscription model as well. Them laying off nearly a thousand people while profit is at all-time high, while CEO gets bonus. All the silly DLCs for SC2. At least they didn't bother with another DLC for Diablo 3 after RoS.
Mike Morheime left for Dreamhaven together with a crowd of entrepreneurs and daredevils. Hopefully he succeeds where Schaefer brothers failed.
Their early games was not made on the sole reason to emulate something popular.