Its true of the HL scene as well to be honest mate - the modding scene in general isn't everything that it used to be. In the past there was a large audience for level review sites and there were dozens of active communities centred around level design. At our peak on the Snarkpit we were getting a couple of new maps, a tutorial, and 50 or so forum posts a day. These days we're lucky to see more than one or two forum posts and a single piece of other content. Odds are the posts aren't even level design related. We pretty much just hang around because we've been here a while and kinda like the place. There's not a whole lot in the way of new blood appearing to reinvigorate things.
Its an interesting turn of events, really. I'd say consoles play a big part, not so much because of their increased popularity (they've always been popular, after all), but because they're now a valid platform for FPS games. There were a couple on the PS1 and N64 that were decent, but they didn't really compete against the big PC franchises. Since the Xbox showed that the genre can work on consoles with Halo, consoles have stolen a lot of that market. Not many big shooters come out on PC and without a consoles version as well these days, and for a lot of people the convenience of consoles makes those versions more appealing. I've got to admit that, in most cases, I'm one of those people.
Complexity is no doubt an issue as well, or at least
percieved complexity. In the days of HL1 mapping you could follow a basic tutorial, get a box room with a light, and see some degree of similarity between what you'd just created and what you'd seen in the original game. Now you do that and you're really still a million miles away. It's gotta be intimidating to first timers, and that discrepency between what you can build after a couple of tutorials and what else is out there on the engine will doubless drive many people away. In many cases it hasn't
really become harder, but in the baby-steps phase it probably looks like there's a damn sight more to learn than it did to us when we were first getting into it.
Another factor, IMO, is that people are spoilt for choice these days. There's so many games competing for your time and attention, so a lot of people probably don't bother spending long enough playing a single game that custom content really enters their mind. If you're only gonna pour 10-20 hours online with a game you'll probably still be finding enjoyment from the retail content. And if you're not really in the market for
playing custom content, are you likely to go looking into how to create it? Not only that, but even if you were interested in creating custom content, if you're not spending all that much time on a single game or engine then it might not seem worth the time investment to learn how to create content for it.
Anyway, rambling now, but it is a rather interesting topic of conversation