When you look at the file system, DVD-VIDEO is just a regular DVD data disc, with some pre-determined files.
So, the burning software only needs to burn the files IFO/VOB/BUP as a regular disc (OK, almost as a regular disc, they do need to position those files at some particular offsets, but that’s all the calculation it needs to do). It doesn’t need to know anything about DVD encoding (in VOB) and navigation (in IFO).
VOB contains the video data. IFO contains the navigation data. The DVD player reads the IFO to decide how to play the VOB.
So, for a software to generate IFO, it pretty much has to know the whole DVD-VIDEO spec (which has 10x more stuff than the file system).
So…my point is, all burning software can burn the DVD with prepared VIDEO_TS folder, but no, even if a burning software claims to be able to burn from VOB only (meaning they generate IFO from VOB), I wouldn’t trust it. I would rather use a specialized DVD authoring software to generate IFO.