Every modifier key starts simple and humble, with a specific task and a nice matching name.
This never lasts. The tasks become larger and more convoluted, and the labels grow obsolete. Shift no longer shifts a carriage, Control doesn’t send control codes, Alt isn’t for alternate nerdy terminal functions.
Fn is the newest popular modifier key, and it feels we’re speedrunning it through all the challenges without having learned any of the lessons.
↫ Marcin Wichary
Grab a blanket, curl up on the couch with some coffee or tea, and enjoy.

I hate when fn is used to hide insert, home or end while ton of space is wasted on useless crap like caps lock.
mbq
+1,000,000
I hate when keyboards hide primary keys behind FN modifiers. That’s the fastest way to obliterate productivity on a laptop! It is so painful and yet more and more manufactures are guilty of doing it without regards to usability and accessibility. Even 15in+ laptops are guilty of doing this where space wasn’t even an issue.
The worst is when the Fn key needs to be pressed to use the F1-F12 buttons and the default is to use these keys for some useless media control buttons (pause, next track, louder). You usually can swap it around (F keys by default, media keys when pressing Fn) in the BIOS settings, but the default is just wrong in most laptops.