I have and currently ride an older Canondale with 7 speed rsx drive train caad 3 frame. I haven’t ridden any newer bikes so I have no basis for comparison. 15 years ago ( the bike is a 96 model) I replaced the front fork with carbon and the wheels with Bontrager select. At the time I felt the upgrades were worthwhile. I am one of those guys that tends to hang onto his toys forever so I usually don’t consider a change easily. I still enjoy riding it as it seems quick and responsive but this is in comparison to my other bikes, which all weigh north of 25 lbs. I doubt I will ever do anything further to it but maintence. I am not a very fast or efficient rider and really wouldn’t get much use out of more gears, as I many times I shift my 9 speed bikes a couple of gears at time. To sum it up I guess it depends on what your goals are, if you are younger and are desiring more speed and performance then certainly a newer bike might be in order. If you are like me and just like to ride for the joy of the ride you may not gain to much. Anyway good luck with whatever you choose to do.