Frictionless and minimalism are related but not necessarily the same. A design can be minimal but still have a great deal of friction. The Linux command line interface is a great example of minimal design with high friction. You can do everything through a single prompt, as long as you know what to type and when. The minimalism is wonderful, but the ability to get going comes with high friction.
Minimalist design is about reducing the surface area of an experience. Frictionless design is about reducing the energy required by an experience.
(1) Product managers should care about friction, not minimalism. Minimalism only matters if it reduces friction.
(2) Cf. How to reduce friction in your product.
(3) Cf. The best products satisfy a frequent user need with minimum friction.