This is what I've gotten out of this discussion too.
As for timeline. I can tell you that when I first started participating in Disney Internet fandom near the end of 1996, there were already elements of what other people would call "lifestyler" behavior. I'm just not sure where others would draw the line.
I spent a great deal of 1997-1999 on mIRC chatting it up with Deb Wills, Deb Koma (although, she was pretty much just a Mom back then...maybe the original Disney Mommy if I really stop to think about it), and the rest of the original crew that went on to become the AllEarsNet team. I wouldn't put them in the "lifestyle" category. They had an interest, better financials or a better location to be able to visit more than the rest, and a desire to inform. but I couldn't say the same about everyone that wasn't hanging on to their every word. People were already rearranging their lives to make their home more Disney, be able to afford more trips, how their personalities could be more Disney. It started before I showed up, but the old RAD group, prior to RADP had already created the Trimobius Disney Cabinet. For most people, it meant you picked a silly name, and put a line in your signature, and that was the end of it. But for more than one person it meant that everything they posted, must be written in a style that supported your TDC persona. Some of it more respectable than others. Anyone else remember Iago and Zazu's Attraction of the Week posts? That was what we had at the time for more detailed Disney info. That, Yesterland, and the infrequent posts from Widen Your World, but Bruce and Ronnie introduced that "character personality" into the narrative. And all the sig conventions of posting how many times you had visited, where you had stayed, originated on USENET. I never got into the Emuck stuff, but I would guess lifestyler behavior was there. And some Disney fandoms pre-date the internet. The Mouse Club, was founded in 1979. And while I'm sure most people were primarily interested in simply finding "like-minded individuals", and sources to buy and sell collectibles, I'm pretty sure there were already more than one person who went far beyond that, based on interactions with people years later in other avenues.
My own "claim to Disney internet fame" was in 1998/1999, my husband and I got upgraded to a night in the Yellowstone Suite at WL. Took a whole roll of film, just "documenting the room" (oh, if digital cameras were just a little farther along) I couldn't WAIT to get back home to put them on my dinky, little website. And yes, people just gushed over it, and yes it was thrilling.
Technology has given "lifestylers" better tools to work with (digital cameras, blogs, twitter). And some of the "expression" has changed. We were part of the NFFC from 1998-2005ish, and while attending conventions you could certainly see that your "worth" could be measured by some in how many Disney Legends would count you as a "friend." Same thing happens now, but we look at it differently, because so many of the true Disney Legends have passed on, or aren't doing well. Saying you were "so lucky" because you spent last weekend at the Davis' house (with both Marc and Alice) instantaneously had more value than taking selfies with random Disney Parks Blogger. If the 90's gang, had had similar technology all of the lifestyler stuff would have played out in a much more apparent way then.