That's not what the Megapatch should be about. This isn't a fix of any kind.
It's more of a recreation for the upcoming new 2001 Mappack Mod since the manhack looked different from that era.
And Megapatch 4 did not include those mappacks. They are separate things. https://hl2-beta.ru/index.php?action=downloads;cat=47
I want to first off say that I do not say this out of any sign of disrespect or dismissal.
However, Cvox, you are very confident in a statement that is so easily proven to be completely wrong.
Megapatch 4 and Megapatch 4.1 had model and texture replacement options for at least 13 separate models. Those include the zombie, the police, the manhacks, the gunships, citizen.mdl, dog, the citizens, the combine soldiers, the buggy, the antlions, alyx, the assassin, and the weapon models.
Additionally, Megabuild, which released 4 months after Megapatch 4.1, was functionally considered to be the "definitive" version of the leak, and was treated by its team as the replacement to Megapatch, DOES include all of those mappacks (specifically the 2001 mappack, the 01-02 mappack, the e3 mappacks, the airex mod, the thing mod, the c17 mod, and several fan packs.)
Now, I understand your concerns. I suspect that you are worried about the upcoming patch being bloated with extra stuff. However, the whole point of these patches are to provide both regular players with functional and accurate assets to play with, AND provide modders with resources to work with.
I do not speak for the other contributors to Megapatch 5, but as far as I understand, the intent with megapatch 5 is for it to be treated similarly to Megabuild, meaning that we plan to have era assets for as many eras as we can have, as well as different options for players to choose from.
If you do not like that, you can just choose not to use the extra things and only use the model and texture remakes for assets that are missing from the mappack, but I can assure you that this model isn't an unexpected addition onto the patch. Megapatch 5 began its development with the the planned scope being that we would not only be remaking missing assets, but also remaking older and alternative versions of assets for the different eras (specifically 2001, 01-02, 02, and 02-03.) We're on schedule for a solid release.