The movie -- it wasn't good. It wasn't terrible, it just had no reason to exist, didn't add anything of its own, and wasn't all that interesting.
Of the sequels, I think Afterlife was a perfectly respectable 'tangential' film (took place outside NY, focused more on Egon's granddaughter, etc.). If it'd been named something like "Spengler: a Ghostbusters Story" I don't think anyone could complain about it being part of the original film's legacy. Otherwise, I haven't really liked any of them (even if some have gotten more criticism than they really deserve). Important to note, I think that's decidedly true of Ghostbusters II--which as a kid I watched on VHS semi-frequently and considered part of the package with the first, but now I look back on and realize is a pretty pale imitation of the original.
The OG cast are really just extended cameos. Aykroyd is in it the most, just tends to pop up in scenes he wasn’t in and just talk like he was there all along. Murray has under 10 lines I’d guess.
Murray has a real problem not phoning it in with things for which he has no enthusiasm. Previously, that meant he just turned down a lot of work. At some point, though, I think he decided that he likes easy paychecks. Between Space Jam 2, Zombieland 2, these past two Ghostbuster sequels, and letting a
T-shirt/NFT store pretend he's their friend, he seems to be doing a lot of low-effort ways of cashing in* on the bizarre fascination** people have had with him for the past 10-20 years.
*Garfield, at least, was him thinking he was slumming with one of his favorite directors, because he didn't know Joel Coen spelled his name w/o an H.
**since Robin Williams' passing, he seems to have been unofficially crowned the elder statesmen of comedy-you-remember-from-your-childhood.
Aykroyd both makes the most sense as the one with real lines, and is surprising in that he hasn't done more in the last two movies. This is still some of his favorite things. I suspect either they don't think people tune in to see him, or he's disagreed with the direction they are taking things and thus he wasn't given as many lines as he'd like.
Alien and Terminator managed quite respectable sequels. But the sequels sort of prove your point; both changed style and tone considerably, shifting toward action rather than horror. They didn't try to catch the same lightning as the originals. Instead, each used the original as a springboard for something new.
They are the exceptions that prove the rules and an example of what to do to make a new good movie (make actual changes). Sadly, enough sequels that don't do that still are
commercial successes, so I guess sometimes the lesson isn't learned.
Then I find myself glad I never watched the cartoon.
I never get on well with cartoons anyway. Confirmation that that's basically what this is tells me why I didn't like the film. And also confirmation that--like most cartoons--I wouldn't like the cartoon.
With the caveat that it is a children's cartoon from the 80s, it is actually fine. Again, it does so by willing to change up genre and framing. It really leans into the GBs as glorified exterminators -- pretty much Venkman and the Green Ghost* in the hotel dinning room scene (much more wacky hijinks than the first movie in total), made into a series. I don't really think the newest films replicate the cartoon, so much as they replicate the stories children made up playing with toys made to cash in on the cartoon.
*which became 'Slimer,' and the protagonist's wacky cartoon mascot character.
They managed four believe it or not since T2. I didn't mind part 3, but it wasn't a good movie at all (just better than I remembered it was when I saw it again). Salvation was awful and Genysis was a different flavor of awful but still awful. I didn't see the Dark Fate because I was too burned out on the franchise by then.
As someone mentioned,
Dark Fate negated/made futile the two original (good) movies, and as such pissed people off. If you go into it with an 'I don't care what you do to this continuity, I'm considering this an alternate reality or something' attitude, it is a perfectly acceptable showcase of Linda Hamilton's acting skills (that still had no reason to exist).