I think their legacy is a renewed connection to the city. As a team and fans, we were spoiled with the team that entered the league. then we had the (alternated definition) spoiling of the team during the 90s, which created a huge disconnect. Even in the early 00's, they still worked hard to sell tickets.
However, that year and team, particularly after the lockout and sports radio/intrarweb, served as the catalyst to attach the atic to an expanded set Edmonton Oiler fans.
This.
EIG had to do a large cash call from the 34 owners prior to the 2004-05 lockout to make sure that the Oilers had enough money to survive. Before the salary cap and the loonie on par with the greenback, the Oilers almost left town at least twice. Anyone remember all the businesses that used to put up "Friends of the Oilers" stickers? The NHL's Canadian Currency Assistance Plan that paid Canadian teams a few million bucks if they sold at least 13 000 season tickets? Remember Superstore bought a few thousand season tickets so that we'd qualify for the CCAP and you could get a pair of tickets and 2 hot dogs for like $50 at Superstore after? Or ATB Financial and the NHL forcing Pocklington to find local ownership to avoid the nightmare scenario of Leslie Alexander's "Houston Oilers" of the NHL?
There were no guarantees we'd still be around as a franchise going into the lockout in 2004 other than the Oilers' history was too important to the NHL to just walk away from Edmonton. EIG bet it all on the last CBA producing some measure of parity and an even financial landscape.
Our city has been through so much with this team. The Oilers gave our city glory, a legendary dynasty, unforgettable memories and the name "City of Champions". After 1992, we forgot what that meant and both sides let a great marriage with the team rot till the divorce papers woke us up.
The legacy of the 2006 Oilers who suffered a heartbreaking loss in Game 7 was so much more than a great ride. They effectively erased any doubt about the Oilers' future in Edmonton. The hate and humiliation we took from players and fan bases across the league after that cup run actually brought Oilers fans closer to both their team and city. Since that run we've proven beyond a shadow of a doubt that we're some of the most loyal fans in pro-sports. It made the team attractive to Daryl Katz and got Edmontonians thinking "hey, what if we had a new arena downtown"?
That Cinderella run in the spring of 2006 was the catalyst.