They very appearance of the books - layout, art, colour - would utterly blow the entire publishing world away. Not just the D&D market, but the whole publishing market worldwise. Colour books? Glossy paper?
Um, Morrus, I've got right next to me a cookbook from 1967. Glossy paper and color photographs, published by Better Homes and Gardens - so targeted and priced for the average home consumer. Folks are massively overstating the change in printing technology.
If anything were to throw people off, it would be the copyright date listed as 2008.
Anyway, I don't think that's the real question the OP wants answered. What happens to the evolution of the game, and RPGs in general, from folks having seen a "finely tuned RPG" early on. I don't think the end results would be as different as one might think, and here's why...
One example of high-tech does not impart a full understanding of physics, and one RPG does not impart a full understanding of game design. Reverse-engineering is more than just taking measurements of every part, and reproducing them. You have to understand the design, and the laws behind it. And that takes experimentation.
So, you sell all your rulebooks, and people play the game. They still have to experiment around that basic design to learn how RPGs work in general. You may give the hobby a leg up by getting more people an example of an RPG earlier, but the communication and experimentation step is still limited by the fact that it is the 1970s and 1980s - the internet isn't there to speed things up.
So, you still get an explosion of various designs some time after you seed the RPG pool. Many wheels are reinvented just like they were today.
I am not of the opinion that the mechanics of 4e are so stunning that they'd come to dominate automatically. There are many other potential systems out there that could have dominated as well if they were given similar market advantage. And while you've handed out a lot of books, you're not there driving development and publishing.
The real question of what games look like is probably a matter of who gains the major market share - and since you've mucked with things, it may not be TSR. I don't think we can predict who does become the big dogs on this scenario.