To be fair, I haven't compared "like for like" hardtails and full suspension bikes. So take that comment with a grain of salt.is that b/c of the breaking bumps? the suspension absorbs them i suppose..
But specifically, this is what I noticed.
I was on a ~2012 26in hardtail XC bike for months before I bought my 2018 Kona Process 153 29'er (again, wildly different bikes).
The first times down the complete front side of Raging River on my hardtail I think my GPS data said I was reaching ~15mph max speeds. Just months later, on the FS bike, I rode the same trails, and reached 20-25mph max speeds. And specifically most of the jumps went from being "how in the world..." to "oh, I could totally do that now if I had the skills".
I feel like now I'm feeling the "flow" of many of the trails much more now, now that I'm riding closer to the speeds that the trail builders likely were envisioning.
Of course some rider progression happened between the few months that I rode the trail. And of course some of the difference was because of 29in wheels, and the geo changes. But I also feel that the suspension helped mute the trail chatter enough that the ~50% faster speeds felt just about as in control as the 15mph did on the hardtail. So yes, braking bumps would be included in that. But also just the general trail noise (roots, rocks, surface irregularities, etc).
I'm sure if I rode a more aggressive hardtail, with the skills I have now (I've only been riding for 2 years, but my first months were on the hardtail... so it was when I was less skilled than I am now, even if my "now" isn't Sam Hill level ), that I'd be faster, and hitting more things. But I still think for the type of riding that is most prevalent around here, that I'd always be more comfortable/in control, faster, or both, on a full suspension bike. Which I think is why almost all racing disciplines are entirely/predominantly ridden with FS bikes.