May I humbly ask what happened to bin/35530?

  I would like to have a means in rc.subr by which an rc.d script can
  give ulimits the command is to be run with.
  I.e., just set foobar_ulimit="-m 999" in rc.d/foobar.

I suspect the lack of response is a combination of:

  While every new spiffy feature, like the one you ask for, is
  interesting and possibly useful, there's also a countervailing
  complexity argument, both in terms of impact on system speed, and
  difficulty of future maintenance.  I think the ulimit feature is
  reasonable, personally.

  There was no patch to implement the variable and properly document it
  in your PR.