Liked Postal 2 as a kid back in the day, not even for it's edginess, but I liked it's open-ended structure. Felt kinda fresh back then.
Tried 4 on PC couple of months back. it's just incredibly boring and trite, which in my book is even worse than it being straight up bad. It's aggressively dated and unfunny jokes made me stop halfway through day 3.
It's kinda weird that it's design and technical complexity stagnated so incredibly in almost 20 years (apart from basic rendering advancements), that it's barely a step up from Postal 2, which I find the only real funny thing about the whole thing.