I do think the nomenclature system is flawed, but in that it needs to be adhered by the entire setting. I could kind of get anything Ketsurui Fleet Yard being the same nomenclature. I could get the Star Navy of Nepleslia sticking to it because their manufacturing was steeped in two decades of Yamatai standards.
Basically, a standard is present because you want to keep track of equipment and you want to stay compatible with it to a degree. If a standard is maintained, then there's a broader organization keeping track of it.
So, across the commonality of mankind, I can kind of get it.
But there's also factions that don't know humankind and have no reason to stick to the nomenclature. They might not even use alphabet or numbers as we know them. Their gear, like Mishhu, might be entirely organic and far removed from our own standards. And then, there could be the organizations out there that don't give a rat's arse about conforming and would rather do their own thing - perhaps even with the notion that they can do better.
...
So, I'm kind of with Arieg. I think the nomenclature guidelines is a great tool for primary factions to follow, but I would make them recommended rather than obligatory. It should be seen as a great tool to maintain consistency if you want it, not a straightjacket. But, also with the caveat that if you break standard, you face certain consequences on the broader market; you could be visiting a quartermaster at Pisces hoping to get components to repair your ship's systems, but then he looks at the nonstandard parts being requested and goes "I ain't got nothin' o' dat. Ye look elsewear fo' dem."
I don't have much against it personally, though I think it's dumb that I'm stuck with the prefix being "Mi" rather than "MLI" for Miharu Light Industries. A pet peeve, but nothing I'll lose sleep over.
But, yeah, I'm posting just because I can relate with Arieg's "this is dumb" reaction. It is. A bit. Or, at least, it's just as realistic as Neo Mishhu painting the alphabetic "NMX" logo on their warships rather than their alien script. Which is: not very much. *shrug*