Alot to unpack here ! I'll chime in my two cents I guess.
I'll be chivalrous and do ladies first. As far as Miriam, I really didnt take her comments the way
@serviceguy did, though I can certainly see how they could sound that way. To me, she sounds smart, like the experienced competitor she is. Knowing your limits is a big part of the game, especially if you want to last for awhile, which she kinda already has. Riding big picture is something all successful athletes must learn. Enter Vali here, as was mentioned by someone in another comment. Finding the line between to send, or not to send, is indeed the question if you'd rather not be just a one season wonder. That's how I took her comments, not as an insult to her competitors , or an excuse for not winning. In fact, I think this very thing is why Camille is seeing rapid success in her relatively short time racing DH. She pretty much keeps her nose clean, putting in solid, consistent runs, constantly improving,while the rest of the field has flashes of brilliance, tempered by gnarly crashes, and repeated injuries.
French Domination: Two major reasons stand out to me, aside from these guys just being incredibly talented riders regardless of anything else. One : Thier country/ sporting and education system, as well as thier culture, takes cycling as a serious, and legitimate sport. This provides young, up and coming athletes with the training and support needed to reach the top levels of the sport. Here in states, we do this for stick and ball sports, but not so much with cycling. Obviously NICA is a step in the right direction,but in it's infancy compared to the European model. TWO, particular to DH, Max Commencal. His factory team puts so much into not just the development of thier bikes, but more importantly, the development of it's riders. His willingness to support several secondary teams, speeds this development process.And let's face it, the majority of his riders are Frenchies.There is a reason Canyon is seeking to somewhat copy this model. It's working.
Bikes: See above statement. Not sure if the Supreme is the "best " bike, at least for every rider, but it's certainly the most developed, with constant input on it's performance from the largest amount of top level riders. They won the race for optimization of high pivot/ idler suspension system, as far as World Cup DH racing goes, and will reap those benefits untill everyone else either catches up, or finds something better. They take DH bikes, and racing, seriously, not just as a loss leader/ marketing strategy. That alone, is in my mind, as important, if not even more so, than the bike itself.