Go back and watch the Die Hard sequels, and make a list of the silly shit in those movies, and place them next to your list of silly shit in Die Hard 4. Is the list longer for 4? Sure, I'm not denying that. But it's still the FUCKING DIE HARD SERIES. If you expected no suspension of disbelief, or even just a bit, then I don't know what to tell you.
I'm really actually surprised that some people claiming Die Hard fans have gotten THIS heated about a lot of the action requiring suspension of disbelief. I mean, sequels DO have to step up the action every time, step up the stakes every time, or people are disappointed. They stepped it up on pretty much all counts. If that's not your cup of tea, then that's fine. But you can't say it's not in the Die Hard tradition.