One could therefore speculate that Han-Ronald Corporation, the makers of the Herc I, was bought by RNI Systems, the makers of the Herc II. Han-Ronald is the manufacturer of a large number of FS1-era ships, but no FS2-era ships*. Meanwhile RNI Systems does not appear at all in the FS1 ships.tbl, but appears many times in the FS2 ships.tbl.
* With the single, annoying exception of the GTB Artemis. A campaign designer could handwave that somehow, or ignore it, or retcon it by changing ships.tbl.
Hmm. I could be wrong, but there's no indication of what year these craft were introduced. Perhaps in this scenario the Artemis was produced before RNI's acquisition of H-RC, and then the Herc 2 came after?
Possible solution:
Han-Roland's assets were mostly located in Sol - esspecially stuff that you don't need redundant capacities of, like R&D; Sol is cut off, assets are lost and the company takes a long time to recover its position as supplier because it needs to rebuild against stronger competitors, lack of investor confidence, having to fullfill previous obligations and/or having to reorganize existing assets for modern use.
RNI by contrast, having it primary assets outside Sol and less previous obligations, would be a highly agile competitor - propably enjoying much more confidence from investors as a result. And therefor being able to recruit top of the field staff and win more important contracts.
(EDIT:side note: that could make the R in RNI stand for Regulus as company origin/HQ - which would also help explain why the "homefront" NTF units in loop 1 seem to be better equipped than the rest)