It often written that top of the line components are less durable (Dura-Ace and XTR for Shimano), with the explanation that they meant for competition and so they compromise on durability to save grams. But is true for all components, or are there components for which this not apply?
- to take the Mx100 cassettes for instance (12 speed Shimano, MTB), the XTR one will have 3 sprockets in aluminium, 5 in titanium and 4 in steel, while the XT will have 2 sprockets in aluminum, and the rest in steel (the 4 small ones having the same part references as from Deore to XTR). In that case, it can be verified, if titanium is less hard than steel. The 4 smallest (steel) sprockets can be replaced separately, so the rest of the cassette can be kept longer, and steel is likely to last longer than Titanium.
- Zero Friction Cycling has done some durability tests on chains, and the XTR M9100 chain outperforms all other Shimano chains — but Dura-Ace 11sp and 9sp are among the worst. The price per kilometer is likely not be the best with XTR, but in these days of black fridays, it's possible to have good deals on this components.
But what about components that wear very slowly: derailleurs, shifters, brakes,...? For example for a derailleur, wear is expected to happen at the pivots, but I would assume that the structure of the parallelogram is where weight saving can happen, and if used moderately, it's not a high stress zone.
So, must the statement at the origin of the question be nuanced?