This has me curious: the MUL has all three of these go extinct after the Late Republic era, presumably because Nimakachi of Lesnovo gears up to produce something else when the Blackout hits, but I'm not able to find out what. It's possible they went back to IndustrialMechs, since that's what was originally built there, but I don't know that that's likely, given the wider series of events at the time.
I suppose it's possible they upgraded the lines to standard Battlemechs, at which point the Wasp line is an easy conversion, at the same tonnage and engine rating. The Wolverine, though, uses a different size engine between its standard and primitive versions, and the primitive SHD-1R Shadow Hawk is only 50 tons, so it's even less of a direct conversion of the line.
For some reason I thought there was some fluff somewhere in a Republic product that did say a lot of the Retro did go away post Jihad when it was no longer "needed".
By either 1 of the 2 reasons you have. Revert to Industrial or Upgrade to Intro.
For the most part it was reverting to support "Stone's Peace".
What your probably seeing is that it took till the end of the Late Republic for the models in circulation to go extinct again over time.
Similar concept to how it took till the 2nd SW for a lot of SLDF designs to go "extinct" even though the factory making them was nuked in the Amaris Crisis.