Do quick release skewers wear out?
 

I already searched online.

I've had issues with my Flo wheels and wobbling, brake rub, and more recently the rear wheel skewer would actually come loose during sprints. At this point the hub was squeaking and the rim was dented anyway and the front wheel was gone from a theft when it was temporarily on another bike, so I just threw it out and bought a set of Campy Eurus wheels. Oh so smooth, so true, so quiet, and no slippage!

I'm thinking somehow the old skewers were worn and not gripping well. Is this a thing? I never had that issue with other wheels.

I guess they could and especially if you take your wheels off a lot from the bike frame. I hardly ever take mine off unless changing a tire or tube.

I've had Easton skewers pop open during a TT, but they weren't old or worn.

More likely to be a lack of/worn out knurling on the lock nuts. The skewer should technically only provide a clamping force, and the knurling does the gripping. I guess an internal cam could wear out with enough usage. But it'd have to be real low quality and be used for years.

Locknuts or whatever they are using to hold the axle assembly together aren't tight. If it was the skewer the wheel would flop uncontrollably and might come out or try to come out in a corner. In other words you'd know. If you can pick up the bike with the skewer tight grab the top of the wheel by the tire and rock it left and right and you can see there is movement by gauging the gap between the rim and the brake pads then you have an axle adjustment, bearing, or hub issue. Next

If your bike has horizontal dropouts, you need to use old style, enclosed-cam quick releases; the modern, open-cam style is designed for vertical dropouts and lack sufficient clamping pressure to secure the wheel.

Regarding longevity: the old enclosed cam units are steel and can last for decades. I have some that are over half a century old and still going strong. Open cam units made from soft materials like aluminum may wear out eventually.