If you’re looking for something about meditation and mindfulness that’s devoid of spiritual interpretations and the like, this is one of the closest approaches I’ve seen that still focused on the meditation aspect and not just generally being “more aware”. It has some helpful suggestions for visualisation, including details not just of picturing things but of feeling things, like his suggestions for standing meditation of imagining yourself as a tree, the part where he mentioned approaching the practice with dignity, etc.
Overall, I doubt it’s going to convince anyone who is highly sceptical to begin with, or help anyone start a practice ex nihilo. But it’s worth reading, and sitting with, and thinking about, if you can put aside scepticism and just try it.
One thing I especially liked was that Kabat-Zinn doesn’t have any thou-shalts and thou-shalt-nots about this. There’s recommendations, suggestions, but also reminders that any moment of mindfulness in the day, however short, is valuable.