Also the real question is would you be faster with a dropper than you would be with out dropper. You are literally a former World class athlete. Sure you can beat some slubs who have a burlier bike than you.
I probably wouldn't be any faster with dropper on my bike then with no dropper on same bike, but I would certainly be faster with some AM/FR bike, dropper or no dropper. As for "some slubs on burlier bike", you don't really need power or stamina on those trails to be fast, so "burlier bike" with more DH oriented geometry is big plus not minus, as there's no pedaling sections or anything where xc bike and rider in better should would give benefit.
I use to set KOM on downhills on 100mm XC bike seat up....once strava caught on those times dropped, and I am now MUCH faster on those same downs in much worse fitness.
what I find interesting is how much easier these average riders can ride the MSA XC course than the mid/back pros who are literally suppose to be the best in the world. watching the XC riders getting back in the rock garden and loosing all semblence of steering.
watching this video and watching people go over the bars because their ego wont let them run something that will make it safer and easier just makes me think XC racers are literally dumb.
I'm pretty sure bikes did change in last decade and again, bike geometry plays way bigger role then dropper, even if in this thread you decided it's only about dropper and dropper is key to everything. Dropper is comfortable but realistically doesn't bring much more then comfort. You get exactly same benefit getting behind seat, with just a little bit more effort, but there's no way to properly compensate for that 5 degree difference in head angle that today's AM/FR/enduro bikes have compared to xc bikes. And exactly that, and not dropper, (plus xc tires which are "a bit" different then what most of you are used to ride) makes problems to those racers you are talking about. Sure they could easy ride enduro bikes on those trails, and I'm sure they would get some 10 or 15sec on downhills, but lose 2min on uphills, so maybe they are not so "literally dumb", as you say.
And those two riding this course weren't riding it with xc bike, which brings us back to geometry again. It's just way more then just dropper