So long as IO keeps adding depth into their game modes, then It’s not bad to try new things gameplay-wise. They just have to be careful about how they go about it. Ghost Mode was fine, but it didn’t have the best balancing in the world, and while I found it fun, it was never really a draw for most players. In fact, it was never officially out of beta, and that’s how it was treated.
My main problem with the co-op mode right now is that, going off of IO’s past behaviour, the matchmaking won’t be cross-platform, which is something that should be a thing by now when it comes to leaderboards. But unless you’re playing via the Xbox/ Microsoft ecosystem, it’s off-limits.
The game is already niche to begin with (hardly unpopular, but it’s certainly not a big franchise, in spite of IOI’s past actions), so adding a co-op mode, no matter how good it is to play, will be hampered if people can’t find people in time, or if friends lists aren’t cross-platform via Steam, Epic Xbox, PS4/5, Switch 1 and 2. And iOS.
Fall Guys and Sonic CrossWorlds have cross-platform leaderboards, friends lists, and cross-platform lobby matchmaking capabilities (though Crossworlds oddly does not have cross-platform accounts, even though you can link all the major providers via the Sega account system – it’s weird). If I were IOI, keeping matchmaking times low would be a big priority for me, otherwise it’ll be abandoned, plain and simple.
EDIT: Apparently I have wishing powers: Cross-Progression is coming to HITMAN WOA and New Look to IOI Account