I don't know, I could see SEGA point of view on all this, I'm sure that they had a big reason on why there was not follow up of VF 5 online after what, 4 years?
They had lots of chances, after vf 5: Online Edition which was the revision C, they released revision d, then virtua fighter 5 R on 2008, 3 other revisions of 4, FS and FS Revision: A. I don't know if the game was a flop or what, but there must be a strong reason on why SEGA decided to not release a new revision of VF5, moreso in a era where fighting games revived from a more mainstream point view on the western.
Hell, some game has spoiled people so much that maybe will not be a good idea to release virtua fighter on disc, people will want a compelling story mode, more extras, minigames, or things like that, and maybe sega knows that they will not afford to make those things to the point of gain some profit of it.
Plus there is the whole stigma that VF is just for hardcore fans (that elitist attitude is harming the game IMO) that the characters are boring, that the game is boring (hell, seth killian buried the game on commentary at EVO when it was revealed that fuudo was a former vf player, and seth replied that he changed to the side where the fun was) and that hardly the game will pick up in western markets (yeah I know that VF4: EVO was a greatest hits and sold like 1 million copies, but Im sure that this was helped for the fact that was a cheap game after a short span)
So yeah, at the moment, we should be glad that the game is released at all, and final shodown none less, hell maybe we could get the latest update arcade next year, even you could think that SEGA is trying to make a quick buck for VF5 or that this is a thank you for the VF community who is really devoted to the game here, there are tons of options, but I could see why the game is DLC, and at the moment IMO is for the better, maybe this will help to create some hype for VF 6 with a full fledged release.
With soe marketing this game will be fine, at least if fighting games fans buy it just because is cheap, maybe it will suceed and gain some more fans