Skins can definitely hold value if you pick the right ones. I've had some for years that actually went up in price which was surprising. The key is getting quality items that people want long term rather than just trendy stuff.
https://dmarket.com/csgo-skins/product-card/desert-eagle-conspiracy is one I picked up recently and the conspiracy design seems like it will stay popular. The dark metallic finish has this timeless appeal that doesn't look dated like some of the flashier options. Plus deagles are always relevant in the game meta so demand stays steady. Worth treating skins as collectibles rather than just cosmetics - some people make decent returns if they're smart about what they buy and when they sell