but i'd bet all of their Iron Man suits are really accurate down to small details.... Alien, Predator, Terminator obviously aren't their main 'let's do this line right' franchises....
I think both your and A-Dev's statements are true tho, aren't they - so it's about the reference they've got. For all the "current" stuff, they've got scans of actors as part of their contracts, they've got availability of actual suit model data for things like Iron Man, etc etc etc. Merchandising is built into many of these shows. But for the old stuff, HT have got Google images, and the pause button on the remote, and then it's just how fussed someone is, and how much time/budget they have.
I'm exaggerating a bit no doubt, but you get my point So, you couple that access/saturation of original data - or not - with the bottom line (and the bottom line is that a lot of what we consider "classic" licences aren't going to make HT anything like the profit the Marvel & Star Wars stuff will), and IMO that combination has got a lot to do with why we get what we get. So you're both right.
Not saying I like it, necessarily. Just I'd say there's a good chance that's how it is.
EDIT - I'm going to pre-empt someone pointing out the current OT Star Wars figures contradict what I'm saying I'm sure HT don't have a load of scans, data etc; but I'll bet they have plenty of time & budget allocated to do the work on those figures, and plenty of Disney/Lucasfilm Archive access if needed, because £££££££££