On the bright side. With Vita and Xperia's Failure, it opens up the door to a PS Mobile device based on X86/Radeon, which would be able to offer a unified OS, Games, and Services with future PlayStation Home Consoles. A future PS5 Portable and PS5 Phone could run the Same OS and Play the same games as the Home PS5. This would mean full support of every AAA 3rd party game. With a unified ecosystem of devices, it would be much easier to support than had PS Vita succeeded, as they won't have to develop for X86 and ARM, and potentially multiple GPU's as well. All in all Vita's failure could turn out to be a blessing in disguise.
The only question that remains. Will Sony capitalize?
I don't think Battery tech and Heat consumption would be able to handle what an x86 mobile device would need. Nintendo went with Tegra for the Switch because it was the only SoC that could deliver what the Switch needed as a platform. It needed to maintain a good enough battery, while consuming minimal heat when un-docked. It needed to be easy to develop for and powerful enough for developers, but also weak enough to accommodate for the aforementioned issues. It needed to be affordable, but also profitable. Tegra X1 was the only chip that could fill this role.
If Sony were to make a Switch-like device, it's almost guaranteed they'll go with Tegra like Nintendo did. Tegra X2 would give Sony's device all the PC-like development tools and engine support found on PS4, while still being suitable for a mobile product, all while being a bit more powerful than Nintendo's offering in the process.