I mean, this is OGs, you are literally prompted to start OG2 when finishing OG1. I don't believe it's such an anomaly for you to have it that the game doesn't account for it in some capacity.
But I can guess that even if you don't have those it still wouldn't make much of a difference, because we return to the same: the earlygame B grade units are what you have and will be using the majority of the game, when your pilots are at their weakest. THAT'S when you need your stuff to be at their strongest. Lategame you get money in the hundreds of thousands and you can invest more freely on the newer stuff.
Notice how in all lf this debacle, no one has stated which lategame units they want to invest on that you absolutely need to save money from the early game to upgrade.
Even the Hiryu, you only really get it for like two chapters if you don't go to the moon, and if you don't aim to get the inspectors secret it's pointless to upgrade it until it joins full time. Same for the Giganscudo.