The cruder the malware, the better your chances of running successfully in Wine.

Because throwing together some simple executable using inbuild windows functions is much easier than programming something well-build and hidden based on deeper system layers. So your random "I just encrypted all your files because you clicked this .exe, now send me bitcoin to get it back"-bullshit might work well on wine (which is why wine should be run as it's own user with no priviledges to access anything but your Windows programs).