I don't really get Matth's reasoning here. It has been canon since FS2 that meson-bombing the nodes is the only proven solution GTVA has in its armory against shivaggedon, it stands to reason that making meson fireships designed specifically to meson-bomb the nodes should become top priority in *any* "Threat Emergency Initiative", much more than designing and building a new fleet of destroyers and carriers, as these will always fail to counter a fleet of sathanas juggernaughts.
Any doubts about whether if these meson fireships may fail their missions or not is academic fillibustering at best, since we all know that if there's a new Shivan invasion, any other tactic has absolutely failed so far (and will again, given the BPverse canon). In that sense, "wasting" fireships is a lot less silly and irrational than "wasting" Raynors and Titans (and hundreds of thousand of lives).
Of course, BP GTVA might have new ideas on how to slow down the Shivans, but that will be a BP novelty that we cannot comment before we get to see it.
e: also:
2) It's not a matter of how many ships you have to fit them with meson bombs, it's a matter of how many meson bombs you can produce to fit them in the ships.
In FS2, despite the technology being brand new, they were able to build and get dozens of meson bombs inside empty Orions within days. Now you are implying that within 30+ years of development of new techs and weapons, the GTVA was incapable of building up ten times this amount - and we are talking about the only kind of contingency that saved them from hell so far.
BP writers are free to write anything, of course. They can say that meson bombs used in FS2 practically emptied their reserves of antimatter that were gathered through dozens of years and that they are so expensive to produce that the Tevs thought it would be wiser to spend ten times its cost in the Sol gate so they could just steal Sol's reserves of it. I'll facepalm a bit, but then, what story doesn't have its quirks?