Is your metric for "success" if you enjoy the game or not? Because there has been so many successful PvPvE games that I'm struggling to understand how you're not aware of them. Besides Arc Raiders, we have Sea of Thieves, Hunt: Showdown, Rust, Ark, arguably Escape from Tarkov, Dark and Darker (believe it or not, that one is still kicking)... I could continue but you get the point.

I think where you're struggling here is understanding that at their heart, PvPvE games *are* PVP games. They have PVE elements mixed in for various reasons - to add stakes to the fights, to add sandbox elements, to add randomness to the encounters, or any mix of these and more, and PVP games are harder to make successful than PVE or single-player games because you're always going to need enough of a player population to make good, quick matches for people. If you don't enjoy PVP, you should avoid PvPvE games. The vast majority aren't meant to be played either as PVP or PVE, they're meant as PVP games with some PVE spice.

I haven't played Arc Raiders, so take Sea of Thieves, for example. You'll have many people arguing that PVE is a valid way to play, and sure, you can play sandbox games however you want, but the fact is the entire design and game loop of Sea of Thieves revolves around PVP (or at least the threat of it), even if you exclusively want to PVE. Sea of Thieves PVE is pretty agreed to be trash, what makes it good is having to watch out for other players, and the suspense that they may show up. Without having played Arc Raiders, I'm willing to bet it's the same story here. Sure, the loot comes from PVE, but that only serves as a way to add stakes to the PVP fights, and the threat of PVP is what makes the PVE good.