It seems to me a bit strange that we are being constantly encouraged to buy stuff from Manufacturer XYZ or they'll stop making stuff. I think there are two reasons they dip their toes and then leave. First is simple, they have unrealistic expectations of a growing market sector. The second is a bit more involved.
There is meant to be a free market where those who do right prosper and those who don't fail. (Except for the banking sector of course where they've convinced governments that they're a special case, and so get bailed out everytime they make a huge mistake.)
If research, tooling and the rest that goes into bringing a kit to the mass market costs as much as is suggested then I'd be pretty sure that I was releasing something that stood a chance of selling. 35th is a well developed cash cow of a scale so niche areas exist, 48th isn't, it's a growing sector so there isn't room within for niche markets yet. What there is can be covered, barely, by the aftermarket suppliers.
The Staghound is an interesting subject but only one variant saw relatively widespread use and yet we have three kits. On the other hand there are vehicles that should have broad appeal if they satisfy the following:
Vehicle saw widespread and/or long term use
Vehicle was subject to modifications over it's service life
Vehicle is well known through film, museums etc to the general public
Extra advantage if vehicle is a German WW2 subject
So, the Staghound fails on all three, the Sherman and T-34 get three out of four and the Panther scores three with extra advantage. So look at the gaps, US Half track, M3 Medium tank, M3 Light tank, Churchill tank (particularily a Mk IV), Centurion, T-54/55 and maybe the M113.
If I was a manufacturer looking to enter 48th commercially I know what I'd go for, and the kicker is that I'm not especially interested in the subject I'd offer! I can see how plenty of others would be though.