I got my KoM* on a distinctly lower mid range alu framed bike, punted along by a (then) 51 year old, 18.5 stone rider with the aerodynamics of a small skip. The next 11 riders in the rankings were all either competitve riders or coaches, all on the latest plastic d***.
You either have the lungs and legs, or you don't, and if you don't then even the most svelte machine won't bestow you with them.
*this was the incident that prompted me to cease using Strava. Without trying too hard I had some dedent rankings on a few segments, and on one occasion got into the top 20 on this particular stretch. Spurred on I had a few dry runs over successive days and then went for it. I had the lines for the corners perfected, and went at it like Stormy Daniels at a presidential reunion. I got the segment, but the moment I had gone past the end and eased off the power I almost fainted, came genuinely close to blacking out while still riding. That frit me bad, so I stopped using Strava so I wouldn't ever be tempted to take it too far.