Have far older bits of kit but in terms of sheer (ab)use - my Camelbak Cloudwalker - bought at least 15 years ago and possibly longer is still going strong(ish).
Had almost daily use for 5-10 years as a commuting bag, default MTB/fell running/small hill bag and also taken packed to the brim on as my sole carry on a few non-physical holidays and day pack for the 'proper' ones.
It's seen a fair few parts of the world.
Just packed it up now to take to the park.
Starting to wear at the bottom and small zip is a bit ropey. Feel I've got my money's worth from it.