I have to totally agree with this train of thought. As a previous Chromag Primer owner and for now a Specialized Fuse rider, there's nothing that my Norco Range 29 enables me to ride that I can't ride on my hardtail.
Sure my line choices are different, my speeds are vastly different, and finally my body also feels very different the next morning.
Riding the hardtail is just a different, more engaging and interactive experience. Maybe if I had the cajones to ride bigger or faster, things would be different on the big bike