I’ve had the exact opposite experience with the darn tough running socks. Mine have been great over the years. I even bucked up and got 4 more pairs so I can wear darn tough every day, no matter what the activity.I have both. Depends on model. Darn tough tend to last longer but can also shrink and become a bit tight over time. Smart wool tends to wear out sooner. My ski socks are all Smart Wool. Some hiking socks are too. My cold weather and hunting socks are Darn Tough.
One style - no show running socks - has a clear winner: Smart Wool. Darn Tough shrink and become too tight after a few washes and also wear out. They suck. All other models are great.