You see the issue though is that Starcraft 1 may have had a bigger impact initially than SC2 (because it redefined RTS so dramatically at the time), yet SC2 is obviously impeccably done, with a great deal of thought put in to dynamics, multiplayer, and of course the map editor to essentially make new games in the custom section.
Not that I don't agree with your point, and forget the graphics, because comparing this on 2 games 10 years apart is silly, but the refinements in actual gameplay, all of the little improvements that automate standard play technique (thinking of worker rally to minerals, stringing actions, etc) make the gameplay of SC2 just as exciting as the first one was when I was playing it so many years ago.
I don't think having it as 86th does justice, they both deserve spots in the top 15, just my opinion