My first impression of OOP, many years ago, coming from C programming: Cool, let's put everything into a class and declare some attributes. These are like global variables but without the bad smell. No more need to pass too many arguments around.
It took me a few years to find out that this is not the real benefit of OOP.
Unfortunately, when looking at OOP code today, many developers still seem to adhere to this mindset.
Unfortunately this is how OOP is still being taught at schools.