The mods for modern games involve making those games better for a specific audience. I've played a bunch of Stardew Valley and Minecraft mods. High-end Minecraft graphics and massive content packs make for an interesting (if buggy) experience.

On the other hand, it's completely different from the Use Map Settings games I grew up playing in Brood War, which were radically different games using Starcraft assets. DotA was literally the same thing in WC3. The game became a game engine. There's nothing like that now. (Garry's Mod?)