It's not that we don't understand the goal, we're just asking why "standard levels" are more important than "levels" per se. Actually playing all levels (both required and optional) would include this movie and have a few minutes of extra content that can't be published on its own. Because extra levels would require a savestate anchor.
"Warpless" usually exists
as a full completion category, where all fundamental but optional in-game conditions are satisfied. For example if "best ending" is the fullest a certain game can get (Resident Evil), we accept it as a separate standard branch. But if there was a way to go fuller by collecting all of some item, or by playing all of the levels, we'd publish that instead.
In this game, there's no warps, so we can't accurately call this warpless. But the player explicitly decides which levels to play, and most of them are optional. So in my opinion, it makes more sense to actually play all levels, optional and required, and have that as a true full completion branch.
Only playing
some of the optional levels may be acceptable depending on the game, but with this game, if we agree to publish this movie, we'd obsolete it with an "all levels" branch if it gets made, because it'd better satisfy the full completion definition.
Lost Levels is different because on FDS, later worlds can be played
from a savegame, and IIRC on SNES, they are all available right away.