I had a chat recently with a fella interested in playing AD&D 1e. He has some idea of 2e and other later editions of AD&D but not 1e. What's the major difference is what he wanted to know.
The more I thought about it, the more I realized that it was more about the specificity of later editions. It's kind of like LEGO kits from when I was was younger. They just came in a big box with a variety of different blocks and a beginning set of instructions on how to build a handful of things like trucks, helicopters, buildings and other fun stuff.
Ultimately, the world was at your fingertips. You could build almost anything you could imagine. Later, LEGO started making kits with specific parts and specific instructions to build what they intended for you to build.
Yes, if you were creative, imaginative and resourceful you could build other things with what was available. It seemed though that while a handful of people (like me) did just that, most everyone else seemed content staying with the provided instructions.
As newer updates to AD&D were released, it seemed as though they were being refined and directed toward someone's pre-determined idea of how the game should be played rather than the wide open and non-directed system that is 1e.
It was like building a specific LEGO kit focused on a specific project instead of building whatever you might have in mind. Sure, easier to referree and run the game but, in my case anyway, it felt like I was playing someone else's game, not "my" game.
To me 1e seems to support spontaneity and flexibility. It allows for a game to go in any direction at any time because 1e has no expectations. It has no pre-determined outcomes. It just the bits and blocks used to build an adventure. Any adventure. YOUR adventure.
Later editions may be fine for other people but they seem too focused and constrained on how someone else thinks it should be played. I'll stick to 1e (and OSRIC) because it feels more like my game, my way.