Mark Dadgar writes:
Would hiring a full-time dev dedicated to MM3 be possible?
To be honest, I don't see how. The money is a small issue, although we'd easily be into 6 figures when all is said and done -- I believe that we could find the money for fundamental Internet infrastructure (I am not joking: much of the IETF itself runs on Mailman). I'm old enough to remember[1] the fiasco when Stallman hired a dev for Emacs and gave him the mushroom treatment. Did not work out well.[2] ;-)
The problem is not contract labor effort; it's management effort (design, prioritization, knowledge of the user base) and mentoring effort (conveying enough of that to the new hire that they can work mostly independently).
Footnotes: [1] This is not the "old enough to remember ..." Twitter meme, this is aged and wizened. And portly, but let's not mention that.
[2] This was before Linux, Stallman was busier than a cat with 3 laser pointers trying to bootstrap the GNU System.