I still say you're giving CG too much credit. There were still awesome special effects in the days before CG. Audiences today might find the FX in older movies inadequate, but audiences at the time, including myself, found them truly impressive and spectacular. Granted, a lot of things would've been harder to do, a lot of FX and action sequences would've had to be somewhat more limited than they could be now, but the movies would work around that. Frankly, modern CGI often makes it too easy for filmmakers to take FX sequences to the level of excess, to the detriment of the story. Limitations are often a good thing for the creative process.
I think the Hulk could've been done pre-CG with animatronics and prosthetics, and stop-motion for the bigger action stuff like huge leaps and tossing tanks. League of Extraordinary Gentlemen
did its Hulk-like Mr. Hyde with prosthetics, only using digital effects to increase the actor's apparent size. Good prosthetic makeup can be amazingly convincing. And it has the advantage over CG of actually being physically real and occupying its environment. (I once went to a museum exhibit of special effects, and one of the displays was a Rick Baker-created ape mask from Greystoke
or some such film, and in repose it looked uncannily lifelike, even up close and in person.) The transformations would've been harder to do, but they'd probably have fallen back on the tried-and-true techniques of cutting between closeups. Baker did some impressive work with prosthetic transformations in An American Werewolf in London, Wolf
, and other projects.
CGI makes special effects easier
, lets them be taken farther. That doesn't mean they're impossible without it.