If someone wants to say that the trailer wasn't funny, and GB was funny, I can accept that. However, in the original movies, only three (maybe four if you count Louis) people were funny. Peter, Ray, and Ego were funny, but the rest of the people in the universe played it straight. The humor was also witty, and not slap stick or in your face. In fact, many of the jokes were over the heads of many kids.
But you just described the formula for most comedies. Most main characters bring the humor while the supporting players/antagonists supply the straight men tactics (but that also requires a level of humor and subtle restraint). In that regard, you can say no one in Animal House was funny except for the Deltas. Plus i always thought the Judge, Lenny, and Peck were all funny assholes.
Either way i think theres still bits of humor in the trailer ; the awkward way Rudd tries to tell them what a “ghost trap” is, the “under the table” line from Finn, and all the destruction from the ecto in the last part.
I think the “feel” of the trailer was to distance itself away from the over the top 2016, and promote the film as an “epic return” to the roots.