Originally Posted by
Lazyass
It's not a night and day difference but a narrower, smaller chain actually is weaker. It's really more noticeable on single speed chains, 3/32 vs 1/8. You won't see track racers running a 3/32.
ZFC testing comparing various Shimano chains finds that successive chain generations last longer. Chain construction, materials and coating have improved.
https://zerofrictioncycling.com.au/chaintesting/
N=1, but personally, I run 11 speed Dura-ace with a good lube, the chain is fine after 6500km+, and I'm not shy to ride in the big ring and crosschain or shift under torque. The last two chains I changed at 6,652.1 km and 6,351.4 km respectively (tracking mileage via Strava), and they weren't worn down to death yet - in the first case I needed a longer chain because I added an OSPW cage, and in the second case I had my first IM coming around and I wanted everything to be perfect.