Of course not. It's an arbitrary line, because the line has to be drawn somewhere.
> It is a highly contentious and political issue.
Most people don't care one way or the other.
> If the systemd proponents would have accepted defaulting to no-systemd, then great, no need for the choice; but realistically, both sides are somewhat adamant, so making the user choose is a reasonable compromise IMHO.
How is leaking internally-facing political issues into the out-of-the-box experience in any way acceptable?!
It's an almost perfect reflection of exactly the reason Joel On Software hates prompting people up-front with configuration options; by refusing to pick a reasonable default, the small number of people who actually care one way or the other are forcing everyone else to deal with their baggage. First-time Debian users completely lack the context to make such a choice, and anyone who does care knows where to look for information on how to switch over a system after it's installed.