JPJ has been getting around a lot (especially mandolin playing). His bass playing is still top notch.
He has stayed active in many different musical genres and actually grown by playing with different people and continuing to evolve. That's why he can still play at the same level or better as in the 1970's, he practices and performs regularly.
You forget Coverdale/Page. The writing on that is top-notch
It was a decent album, but the best song, Shake My Tree, was a holdover from the Presence sessions. Obvious similarities to Nobody's Fault But Mine as well...