I'm always surprised when people get so actively worked up about people liking something they don't. MGS4 isn't perfect, it has some very major issues, but it's incredible in so many areas that it's worthy of praise, as is GTA4, as is FFXIII, etc.
In a way maybe it's a testament to those games that they can instill such passion in polar positions. Ultimately any of those heated debates come down to someone stating something is objectively bad, because they don't like it, and someone else saying the opposite, both looking bad. I think Super Smash Bros is garbage, but I accept people adore it, as bizarre as I find that. People care too much to ever have discussion about those games go well.