I will disagree here. I do agree that Islam is very “holistic” as you say, in the sense of being totalizing. But I actually think that Buddhism and Hinduism are much more deeply rooted in the West, and they are just as demanding, albeit in different ways. They are also slightly more covert in that they can take root without necessarily being identified as a religious belief system.
How many people today practice mindfulness meditation, go to yoga classes and abstain from meat? These practices are even seamlessly integrated into corporate boardrooms and public educational institutions. Granted, they might not accept Buddhist dogma or have a guru, but they’re definitely going to be more receptive to Eastern philosophy and spirituality. And in these systems, there is no division between a private religious life and a secular public one, we just don’t recognize it as religious behavior because we expect certain rituals that it lacks.