Just to give my personal opinion on the subject...
I don't think there was ever an old tried and true marketing plan that worked wonders for the ISU or USFS and then stopped working.
The sports federations first priorities are to the participant athletes, not to viewing audiences.
If we're talking about marketing, we're talking about potential target audiences. There are a number of different target audiences that skating federations might address. For example:
1) Casual viewers who just want to tune in and be entertained, maybe buy a cheap ticket for a local event that showcases top skaters they've already heard of in a two-hour package, but who don't want to need to do any outside work of their own to enjoy an occasional performance.
2) Skating fans who want to follow the sport from week to week during the competition season, year after year, who want to learn more about the competitors and the technique and the rules of the sport, who might be willing to invest more time and money to watch many hours of competition in person if one happens to occur locally or even to travel to an exciting event.
3) Recreational figure skaters who enjoy the sport at a level that does not demand a huge commitment of time and money
4) Competitive skaters who devote years of their lives training many hours a week in hopes of reaching elite status
Category 1 is where significant amounts of money from outside the sport could be directed into the sport. In the 90s, a bunch of factors came together to make that happen. Most of those factors are no longer applicable.
I think the increase in interest in the 90s was due to a convergence of many factors, most of which had nothing to do with marketing. As the US public's interest in figure skating declined, and as the media landscape changed with the way performance or sport as viewing entertainment is delivered electronically, the federations have adjusted their marketing to audiences to deal with new realities. Those changes haven't been enough to overcome the waning interest, but I think that viewership would be even lower now if the same marketing techniques were being used now as 15-20 years ago. The conditions that produced the unusually high interest in the mid-90s no longer exist, and most of that difference is attributable to the reality of changes in the world at large, not the fault of the skating establishment.
I suspect that casual audiences who don't want to work for their entertainment would be best served by a sport that featured the same 10-20 top skaters per discipline, all trying the very hardest technical elements and/or with the best professional-style artistic polish, year after year, so they could tune in once a year or once every four years and still expect to see their favorites, with only a few newcomers at a time to keep things fresh. Good for marketing to the casual millions, but death to the development of the sport and the up-and-coming athletes.
Regarding category 2, I think that the Internet including places like Golden Skate has done a lot to build a knowledgeable fan base. Federations could reach out to fan communities even more and try to work with mass media such as television to encourage casual viewers to become knowledgeable fans.
Still, the diehard thousands aren't going to pay the bills. Are there really millions of potential fans out there who want to put in the effort to learn the sport inside and out?
If we want to increase the general popularity of figure skating in American culture at large, I'd think one way to do it would be to increase the number of Americans who fit into category 3. Once people have a basic familiarity with figure skating in their own lives, they'd have a built in interest in watching the really good figure skaters show off the elite state of the art. But that's easier said than done.
Access to ice on which to learn and practice is always going to cost money in the summer, and very few people live in climates where natural ice of a quality sufficient to train in winter. So by nature ice skating is always going to be a more expensive sport than one that can be practiced on any available field, or one for which a court can be built at some initial expense without expensive daily maintenance costs. Compared to tennis or basketball or even swimming, it will always be a niche sport. How much can its niche be expanded?
I think that US Figure Skating has done a lot in the past 20 years to welcome recreational skaters into their ranks and to retain would-be competitive skaters once it's apparent that dreams of elite success are unrealistic. The approach is not nearly as elitist as it was in previous generations.
For example, see the discussion of membership numbers near the top of this page and the links to various programs toward the bottom.
http://www.usfigureskating.org/About.asp?id=13
I can't find similar membership numbers for Skate Canada; I think the total numbers are comparable or a little higher than in the US, and of course their population is much lower. But ice sports are much more a part of the national culture. Here's a list of Skate Canada's recreational and competitive programs:
http://skatecanada.ca/Development/ProgramsSchedules/tabid/205/language/en-US/Default.aspx
If there were a big chunk of money available for marketing skating to potential participants and giving a chance to try it for free, there might be a way to attract lots of people to the very lowest levels of the sport. But beyond one or a few promotional events a year rinks will always need to charge money for use of the ice, and they can make more money selling ice time for public skating or usually hockey. And unlike many other sports, at a minimum it takes a few months of lessons and practice before a beginner can graduate from learning to skate at all to learning to figure skate. And the more serious they get about the sport, the more it will cost to keep improving skills, let alone traveling to enter bigger/more important competitions.
The state of the U.S. and global economy in general will affect how many people are able to maintain recreational or competitive skating as a hobby, no matter how well it's marketed to participants.
