It's not that JRPGs are dead. Some could argue that they're dying, but given the loyal albeit niche followers, the sub-genre probably (hopefully) won't disappear entirely.
However, the days of big-budget JRPGs may be gone. I just can't conceive of huge AAA JRPGs on the next-generation platforms. What we already see in this generation is that most are obviously on the lower budget end of development. This is primarily why they haven't matched up with the rest of the industry in terms of technical proficiency, and why in turn they have fallen from favor in the eyes of many critics.
Unfortunately, these days, most see JRPGs as either strictly for kids or mostly for the anime fans, which hardly constitute the majority of gamers. This is a very different ecosystem than it was fifteen or twenty years ago, and we have to accept that. One could argue that Final Fantasy will always be big-budget but at this rate, we probably won't be able to call future installments in that franchise "role-playing games." Lightning Returns: Final Fantasy XIII might loosely qualify as action/RPG but there's almost no doubt that Square Enix is taking a more action-oriented approach with each new installment. Nobody knows why , but whatever.
Beyond that, what is there? Does everyone remember when Legend of Dragoon was being advertised? The number of people working on it, how much money it was costing, the sheer amount of time spent in development, etc. The game eventually shipped on four CDs and although it didn't exactly bring down high review scores, it was widely regarded by many JRPG fans to be fantastic. I just can't see JRPGs having the same budget and workforce behind them anymore. No team is going to risk losing a ton of money on a big PS4 title, not when the common belief is that JRPGs just aren't popular enough for a significant return.
Sadly, I think smaller niche productions are the most we can hope for, and I think the majority of any JRPGs in the new generation will be digital-only or designed exclusively for handhelds.