Apparently there is a least one dev (the one that maintains udev) who has gone on the record as saying: "I wouldn't mind systemd becoming the Gentoo default, as I see systemd becoming the norm in Linux userspace, but that hasn't happened yet, and migration will need time." I am loathe to put words in the mouths of non-native English speakers, but it seems pretty clear from that post what kind of pen he believes that we should all be guided into.
I personally find it odd that he claims to have no dog in this fight, yet seems to be on the side of SystemD taking over everything. He also doesn't seem to mind when Poettering tells him point blank: "Unless the systemd-haters prepare another kdbus userspace until then this will effectively also mean that we will not support non-systemd systems with udev anymore starting at that point. Gentoo folks, this is your wakeup call." It's all water under the bridge to him apparently.
Even giving the dev the benefit of the doubt, it seems to me that he's fighting a losing battle as Poettering has made it abundantly clear that he wants udev sans SystemD to die, and it seems that he is indeed doing everything in his power to make it so.
At any rate, I don't wish to derail this thread any further, so I'll shaddap now. :)