This century has seen 2 revolutions in computer hardware: LCD screens and SSDs. In terms of computing, SSDs promised an order of magnitude of speed improvement, with greater reliability.
But in technology, the panacea is rare. Besides their lower capacity / higher cost, a decade after they became mainstream, SSDs remain harder to diagnose. And even with maturity, their reliability is quite comparable to HDDs'.
SSDs are a revolution which is still ongoing, but as computers mature, engineering them is more and more a matter of trade-offs.