This LA Times article observes how Saturday Night Live has been able to endure for nearly 40 years despite the fact that it's top talent regularly moves on to more lucrative ventures. It's basically the durability that MLS is looking to create...and already has in some ways.
Except, of course, that MLS and SNL have almost nothing to do with one another and nothing in common. Reading the article confirms this entire lack of similarity. SNL has endured for 40 years because it was once culturally relevant and, in fact, was virtually the only game in town (late night variety/sketch show). There were a few imitators, but nothing was very good. Now, it is a cheap show in a cheap time slot and is mostly ignored (Tina Fey as Sarah Palin notwithstanding). They also seem very comfortable as they are, drawing significant enough to stay afloat and are still able to draw big acts. MLS started as a teeny minnow in a big pond and has grown into a small fish in a big pond. MLS wants to improve, and improve by leaps and bounds. SNL is what it is and nothing more. SNL is still pretty much the only game in town for what it does, to the extent that anyone cares about SNL. If SNL were like MLS, it would have signed some major international stars on the downside of their careers to bring notoriety to SNL, as MLS has done with Beckham, Angel, Henry, Blanco, et al. SNL would have signed, say, John Cleese in the late 1980's, Rowan Atkinson in the 1990's or Christopher Walken 10 years ago. Best they had was Billy Crystal who was a decent sized star before joining SNL. If SNL was like MLS, there would be an SNL version of Tim Howard, Brad Friedel, Brian McBride, or Clint Dempsey (or even Ryan Nelson), a star in MLS who went on to star on the biggest stage of all. Or even a Landon Donovan, who stayed in MLS and was a major player in the World Cup. Chevy Chase had a couple of okay movies and nothing. John Belushi could have been a huge star if he had not imploded. Dan Ackroyd had a decent career, I suppose. Tina Fey has a good tv career. Adam Sandler made a career out of making nothing. I guess Eddie Murphy and Bill Murray went to major stardom shortly after SNL. Mike Myers and Chris Rock have had good careers. Frankly, there are very few comparisons between SNL and MLS.
SNL is not like MLS, SNL is like the Columbus Crew. Note, I don't mean this at all as a criticism of the Crew. SNL v. Crew Virtually the only game in town (only summer pro team in Columbus). Relevant to its audience, but not really relevant nationwide (the Crew are not LAG or Seattle in terms of popularity). Occasionally succeeds greatly (won one MLS Cup). Occasionally has someone who goes on to bigger things (Friedel, McBride). Never signed a giant star to put them over the top, but finds an occasional small-stage star (Stern John and GBS, for example). Almost always competitive, if hardly great (have only failed to make the playoffs a handful of times, 5 or so).
Not really. The musical acts are more like the high profile friendlies that MLS teams play against big name teams. Lady Gaga playing on SNL is like Seattle playing Chelsea (or the Fire playing Manchester United last year). The big name comes in, some extra people tune (or, with MLS, show up that night) in to see the big name and then disappear.
The biggest parallel I see between SNL and MLS (i.e. what made me post this here) is the feeder league nature of each one. True, they're entirely different crafts, but they've both managed to find and hold on to a niche despite losing their best talent and in turn not necessarily being the best product out there. The most striking difference between SNL and MLS is their aspirations, as you noted here. I'm not sure if SNL ever had that upward motion mindset that MLS currently holds (I wasn't alive back then) but if they did it's been gone for a while. Hopefully the 37 year-old MLS will manage to retain its youthful exuberance. I think you're setting a much higher standard for our MLS alumni than what the record shows. First of all, all four of that top MLS products you named (hell, 5 including Nelsen) may have spent their post-MLS careers in the Premier League, but that does not necessarily put them on the biggest stage of all. That biggest stage would be the UEFA Champions League (may eventually be the CWC, but FIFA hasn't figured that tourney out yet). Of those five players, only Howard has seen UCL play. I'd say that evens out the comparison.
SNL v. MLS Virtually the only game in town (MLS is the best in-person soccer product around, but with the tech we have these days this argument is conceded). X Relevant to its audience, but not really relevant nationwide (MLS's in-stadium attendance vs. National TV Ratings). Y Occasionally succeeds greatly (RSL's near miss last year, LA and DC back when 'home & home' meant two home matches). Y Occasionally has someone who goes on to bigger things (Friedel, McBride, Howard, Dempsey Nelsen). Y Never signed a giant star to put them over the top, but finds an occasional small-stage star (Beckham breaks this argument. Conceded). X Almost always competitive, if hardly great (mixed CCL results, mixed friendly results. If 'competitive' means almost winning all the time, then yes. Otherwise, conceded.) (push)