For much of 5e’s early life, the Archfey patron was the Warlock’s fun-loving, tricksy, potentially goofy option. Since fey are often capricious, unpredictable, and weird, it makes sense that warlocks in the same vein would be, too.
While it has never been as popular, as powerful, or as attention-grabbing as some other warlock patrons, it’s still a lot of fun both thematically and mechanically. It also doesn’t deviate much from the core of the Warlock’s features, so in many ways it’s a better baseline warlock than the Fiend. If you want to get a good handle on the Warlock’s core capabilities, or if you just want to get into some goofy fey nonsense, the Archfey is the way to go.