Yes, the major benefit of Dev Drive is that the default filter driver stack is minimized from OS drive defaults, including Defender's and other AV's realtime drivers. NTFS itself wasn't the problem. Microsoft seems to acknowledge that the filter drivers in the wild are a part of the problem, and a partition opt-out is useful. (Of course all those warnings about corp group policy also point out that Enterprises are given the ability with group policy to force turn on a lot of those filter drivers for Dev Drive partitions, because Microsoft loves giving Corporations ways to shoot their own feet in Group Policy. What would Group Policy even be if it wasn't just Footgun as a Service?)

It does seem like this is some sort of "trojan horse" (but not in a bad way) play for ReFS. But I'm not sure it is for sinister reasons: Encouraging Developers to use ReFS for their main development partition is a good way to encourage lots of free app compatibility testing on top of ReFS and suss out the minor bugs in applications that assume all Windows runs solely on NTFS. It seems like a play to increase reliance on the VFS layer and its abstractions and further get away from code assuming NTFS specifics.