Yes, but you can't put Simon's Quest or Vampire Killer in the same group of the 7 MetroidVania and the 2 3D MetroidVania, which we all know what games they are.
Also, there's middle ground that leads to confusion. Vampire Killer is based on exploration but is also a level-to-level game. And Rondo of Blood is level-to-level but allows you to backtrack anytime you choose a level, and features a game percentage display. Nevertheless, it is part of the ClassicVania in the popular vocabulary.
And the Lords of Shadow games (1 and 2) feature similar characteristics to Rondo (in terms of always allowing stage selection and having a percentage display). Mirror of Fate could be a MetroidVania, but it's lacking several things from what everyone knows that must be in a MetroidVania.
Long story short, we call MetroidVania these games: SotN, CotM, HoD, AoS, DoS, PoR, OoE... CoD and LoI in 3D.
And ClassicVania to everything else, with the exception of the MS games which are self-contained, and the alternative games (1 cell phone game, 3 Pachislots, Arcade game, a fighter and a multiplayer).
That's how I see it and I believe it's pretty accurate.