>>719680885 (OP)
It had plenty of silly, light and comedic moments. The over all situation was more far-reaching, chaotic and dire for multiple individuals involved though.
A whole PMC rebuilding after a takedown plot, dealing with other PMCs, former allies, etc. Quite different from a small, elite team squaring off against another and in many cases having no prior encounter.
Snake and Raiden weren't previously one-upped by most people they took down in the games, although once you get to MGS4 there is history with some enemies and things got darker as a result.