There are still plenty of hospital-based diploma schools around, but, as noted, far fewer than there used to be. Some states no longer have any diploma programs at all, but there are also places where they are still popular (I recently relocated to PA, and PA seems to have as many diploma programs as the whole rest of the country combined
). North Carolina, where I spent most of my career, is down to just two in the entire state (but both of those programs are going strong). It just varies from state to state.
I graduated from a diploma program many years ago. Since then, I've completed a BSN and a Master's and have taught in ADN and BSN programs. I must say I got a much
better nursing education in my diploma program than students in any of the ADN or BSN programs with which I've had experience since then have gotten.