Because not specifying a version assumes the DOS version. This is again version specific, but without saying. That's more unfair than actually specifying one.
People, please remember that Lemmings was/is commercially available on over 30 platforms. Not everyone played the DOS/Amiga versions first. Me and Adam played the Sega Master System versions first. I know somebody who has only played the SNES version.
Each version has its own peculiarities centred around the mechanics and redesign of certain stages. To ask the question "What level features three giant numeral sixes?" will not even make sense to somebody who has played the Macintosh version which is a fairly standard port. Or to ask the question "What level has an alternate tileset based on the game 'BEAST'?" would make no sense to somebody who has only played the Windows 3.1/95 version. Even questions about skills may not transfer, such as the one I answered earlier about the Slider in Lemmings 2 (the Game Boy version has no slider).
So, most questions you may ask will be in some way version specific. The reason why it seems more pronounced lately is because we're bothering to mention exactly which versions our questions apply to. After all, the first level to have more than 20 builders probably varies (the NES version never gives more than 14 skills, for example).
There hasn't been some increase in questions. We're just being bothered to be clearer on what we mean. In the end, this can only be a good thing.
I appeal to everyone, if you want to ask a question about DOS Lemmings,
say so. It is not fair to make us assume DOS Lemmings if we are unfamiliar with it.
For the sake of repairing an interruption, I'll repost Adam's question:
On the Sega Master System version, which is the first level to have more than 20 builders available?You can find the answer at
http://www.youtube.com/SMSLemmings, Adam's YouTube resource for Sega Master System Lemmings. To cheat even further, check out the playlist at
http://www.youtube.com/view_play_list?p=58CD920B2A89D2DB.