Mantling is completely different. TLDR Mantling is when you embody the attributes and actions of a deity so well that the universe can't tell you apart. "Walk like them until they must walk like you."

I'm not sure if any of the Walking Ways specifically rely on accumulating followers or worship, actually.

If you subscribe to the not-entirely-confirmed theory that the Thalmor are trying to destabilize the Mundus by stamping out the worship of Talos, you could sort of argue that they're trying to do the opposite of this - de-canonize Talos/Tiber Septim by depriving him of followers and/or worship, but that may actually require killing all Men, not just stopping Talos worship...