systemd may be nice but it's coming from Redhat and cgroups are changed due to because systemd folks wanted it that way as far as I followed that debate...
Ted Lemon (the author and maintainer of ISC DHCP from its inception to 2003 [0]) asks for the location of the project's source repo. Sievers replies with a LMGTFY link that doesn't even answer Lemon's question. Lemon politely criticizes Sievers for his rude and unhelpful answer. Sievers fails to even apologize.[1]
Both Sievers and Poettering have pretty serious attitude issues. It's one thing to lambast a peer who frequently fails to meet the potential that they've demonstrated in the past. It's entirely another thing to try to score social points with your callous indifference and blinkered bullheadedness.
[0] https://www.isc.org/downloads/dhcp/
[1] Check the first few comments of: https://plus.google.com/+TomGundersen/posts/eztZWbwmxM8
The project being run by people who hold unreasonable and downright odious views who act like, frankly, utter asshats, is a much more serious problem.
The Kay/Linus debacle is something you can expect to see more of from these fine folks going forward. Mark my words. Ask yourself if you want software developed this way running your OS.