If you had to pinpoint a trend in popular film for the latter part of this century the fondness for producing sequels would certainly be noticeable. It's not that the sequel was invented in the last 25 years. It's just that it has definitely been overused.
Some sequels are an improvement.
On the other hand, many, if not most sequels do not measure up to their original models. Computer technology sequels are even more frequent than film sequels, except with computers we call them upgrades. Sometimes it's hard to tell if the sequel is an improvement over the original. The usual elements are there, but they supposedly act better. The difference with technology is that its ongoing march makes upgrades, if not necessary, for the most part desirable.