Headphones

Two wireless: one consumer level with active noise cancelling, one that's heavy with shit battery life but uses tech to sound closer to wired. They legit sound amazing over Bluetooth but whatever tech it uses only has line a 5 ft range and nerfs the battery from about 5 hours play time to like 30 minutes to an hour.

Three open backs: one bassy, one flat, one high grade (but too heavy to move around with much)

Two closed backs: one planar for a bit of separation, one "fun" that works great with EQ but is objectively a mediocre headphone. Really great to use for games.

None of my headphones were bought for over 500 dollars, and sure I could EQ some so sound similar, there's always something about each pair that another can't quite replicate, even with EQ. Like, you can't just add haptic bass like the Skullcandy crushers have. You can't increase sound stage well with EQ so open backs are always a bit better for that. Fostex T50RP Mk3 with Dekoni pads have a lot of planar positives, but can be EQd to basically be "planar bass cannons", or as close as planars can really be. AKG k712 are great for mixing music and things, but are basically objectively bland for actually listening for pleasure. They're basically work headphones. My "daily driver" headphones are closed back Hifiman Sundaras because I like their sound a lot for everything from games to music.

Not everyone needs multiple headphones, and not everyone wants multiple headphones. But to pretend like EQ makes all headphones perfectly equal is disingenuous, and all headphones do tend to serve different purposes.