In a word no. Rolling Stone is very biased to people they like and will simply overlook any artist that that particular reviewer thinks is bad, bad for a personal reason.
The two biggest influencial acts since 1955 are Madonna and the Beatles.
But you can easily see the difference.
The Beatles entrance upon the scene CHANGED the rock era. The music of the Beatles changed the direction of music to the Beatles and European sound. This change was not as rapid as we think. Indeed after the inital invasion by the Beatles, Bobby Vinton had the last number one song, before the first number one song by the Beatles and their string of #1 hits was ended by Louis Armstrong’s cover of “Hello Dolly.”
Madonna on the other hand capitalized on changes. She was brilliant because she could spot the direction music was taking before the change took hold and was able to adjust her music to capitalize on that new direction. Her songs didn’t CHANGE the direction of music as much as they just anticipated the new direction and did it better than others.
The “Rock Era” started to wane in the late 80s and was dead by the end of the 90s, though people are loathe to admit it. By 2004 every single #1 song was by an R&B artist. This is clearly a shift in pop music from “the Rock era” to the “R&B-Hip/Hop-Rap Era”
Mitchell was a good songwriter, but her style hasn’t changed. And while she writes well she pretty much does for “message songs” what Dianne Warren does commercially. Basically writing the same song over and over. Mitchell’s songs are all very similar sounding as are Warrens. You can easily see Judy Colliin’s “Both Sides Now,” is a Mitchell written tune. It’s sounds just like it.
“Influence” is too big of a buzz word. Tons of artists say “Bob Dylan” was an influence on them, but how so? He certainly has had limited commerical appeal for a man who gets quoted and referred to as influencial.
It’s hard to be an artist that changes the direction of music consitantly. It’s easier to be one that is able to see changes and adapt. Olivia Newton-John is another female artist that was able to span the entire 70s consistantly because she could adapt her music from “Soft -> Country -> Disc -> Dance.” Her contemporaries Helen Reddy and Karen Carpenter, failed to keep up in the later half of the 70s while her latter contemporaries like Donna Summer didn’t have the indent in the early 70s, while finding their niche in disco. Yet Olivia Newton-John popularized two of the most carried over trends in music, “the breathy style of singing” (from the first part of the 70s) and the “screach” from the latter 70s. (You can see this on her “Come On Over” CD where it’s amazing the strength of her voice, 'cause your used to hearing her all weak and breathless"
Look at Elvis. His influence was really greatest AFTER he died. Before then people wanted to simply copy him to make the money he did. Ironically Elvis (or rather his estate) was much more popular and influencial and made much more money after his death than before it.)
So when you look at influence it’s really subjective and it depends on how you look at it.