I forgot to answer the question earlier.
I hate the use of the terms overrated and underrated on the internet. Overrated is far more used.
They're so overused the actual definition of the words have been lost, much like other words that get overused.
The word 'overrated' gets thrown around so much in a negative sense to declare something bad without the nuance of it. I think it's more accurate to call something you enjoy as 'overrated', rather than using the word negatively. For example; I like Judas Priest's Painkiller album quite a lot, but I'd say it's slightly overrated compared to their other great albums.
Since games were mentioned, one thing that bugs me on internet discourse over games is when one new installment of a series disappoints the fans, and then there's this revisionism to declare the previous game "actually underrated". Batman Arkham Knight disappointed people, so then Arkham Origins was declared great. This has happened with every single Zelda title going back to Majora's Mask. The entire reason MM became beloved on the internet was out of disappointment to Windwaker. Then the same thing happened for WW after Twilight Princess and Skyward Sword disappointed some fans.
I also find it weird how certain big game titles have become hated by the popular opinion of internet majority. Quake 2 was a critically acclaimed game when it first came out, and was rightfully praised for it's graphics and gameplay. Now it's laughed at and often called "Id Software's worst game". Even the most dedicated Q2 fans now call it 'underrated' regardless the irony of it being a major game that people run out and upgrade their computers to play. It feels weird calling Unreal 'underrated' given it's critical acclaim and importance in PC gaming, but the way it's been forgotten and almost lost in time, makes it that.