This discussion is futile because people have no real understanding of just how much a game's data can be pseudo-artificially enlarged to ease development. Of course having the ability to do so is a good thing. Just like getting a decent performance out of your graphics chip without having to involve the cpu is a good thing as well.
Data layout and organization are a significant part of game engine design and if you expect a lot of space to be available, you can efficiently cut corners by say - just as an example - put a copy of each used texture along each individual level that uses it even though they effectively become duplicates. Just look at the size of the downloadable content for oblivion and you get the idea.
I can assure you that there is no way that MGS4 could not have been made to fit onto a regular DVD (nonsense like lossless audio aside). It's a matter of effort, though I assume if your dev team has never worked on anything besides optical media, that's just the way they learned it. Doesn't mean it's the only way. For people working on GBA or Mobile games, it's a severe issue all the time. Different backgrounds, different solutions.
Yet, for some reason, not dealing competently with storage space limitation on high end platforms is less frowned upon on this message board than other development inconveniences/burdens - like having to spread out your code onto 7 mini processors with their own little address spaces.
I suppose the actual blame for this tedious discussion is to be put on producers that look at the size of their data folders in windows and go tout nonsense like game x wouldn't fit on medium y due to its shear size (while their engineers are probably well aware that it could). Probably also on journalists for passing this stuff on without questioning anything.