Okay, time line:
Lightning was better than Storm, Quetzalcoatl and whatever the heck else was on the tier list at that time. It wasn't a consensus then, I remember fights about Storm vs. Lightning (Smash-wise, obviously Lightning was wayyyy better, still.) McFrown was pretty much the only one (+ Capt. Squirrel) who advocated Lightning and how it was WAYYYYY better than Storm.
Next big thing was probably Pegasis resurrected/Vulcan. By that time McFrown had people thinking Lightning was the best wheel of that time, won the war on Storm. (he was right, too. I remember him advocated Lightning all the time>Storm)
People were comparing Vulcan to Lightning, and McFrown thought they were about even. (+ he slayed Quetzalcoatl) I'd agree with that. Gravity came up, yeah, but didn't make a giant impact for some reason until later. (probably Vulcan's fault.) As soon as we moved to Rubber tips/230CS combinations Lightning was obviously the only choice. (Gravity was still sort of in the dark iirc..)
Now lets say Basalt BD145CS/MB? Anything that isn't Beat, Blitz or VariAres can consistently KO it to my knowledge. Meaning Gravity and Lightning are far in the dust now. Which they are, smash-wise.
IDK if this makes sense to you but basically after all of right-spin died due to rubber bottoms, Lightning was the only competitive choice (Gravity wasn't main-stream obviously, but I don't think it has as much smash as Lightning anyway..)
Basically what SSJ said. But yeah, since it's release it has been extremely prominent which cannot be denied..