TBH it's not a *need* at all. I'm certain that with a new hot end fan (to cure an annoying buzz on startup that goes away after c1min) and some fettling the ender 3 would soldier on no issue, its definitely more of a want. So my *want* factors
Want always = NEED

- not fart-arsing around with a USB/micro SD card any more when I want to print (biggest want)
Virtually all have remote printing now, either via cloud or via LAN, or both. Creality Flagship series do both. I do personally seem to get a lot of occasions when the printer seems offline on the LAN, but still online on Cloud, which I think is due to the Wifi briefly disconnecting. I keep meaning to try a cat5 instead, as I do live in a very, very hostile WiFi area.
- filament enclosure so that I can be lazy during machine down time and not bother removing and storing reels of filament properly.
CFS can do that, *BUT* it's dried via desiccant. I use desiccant crystal that can be reactivated, which I have to pop them in the microwave every week, or more often if I open the CF too regularly to swap spools.
- enclosure to reduce noise - it shares swmbo's office and it's annoying enough to her that I don't print while she's working - which definitely slows production
K1 Max was noisy, I think the way the idea fan was mounting on a perspex side. K2 is not silent, but seems les intrusive *except* nozzle wiping and CFS feed/retract. Mine is in the box room office I work from (as was the K1, the brilliantly named Artillery Sidewinder X1, and the very noisy Anet)
- enclosure to stabilize temps - we don't heat that room at night so ambient temps can drop to mid-to-low teens this time of year which I wonder if could be affecting reliability
Enclosures also help with other filaments such as ABS. My office stays fairly warm due to all the other shite running, so even recently, hasn't gone under 15C. K1 has fan to cool the chamber, K2 has an active heater as well. In both cases, you will need to print a lid riser, and I'd recommend one with vents that can be opened and closed, leaving open for long PLA prints, esp on warm days.
- direct drive and enclosure to allow me to confidently venture beyond pla. Not sure what for yet, but I'm sure ideas will present themselves, just like they did when I got the ender 3.

- better quality to allow me to print scale models - very low level want as I suspect the money spent to improve quality would more than buy a cheapish resin printer that would give vastly superior results.
If you are talking about models to print and paint and display, resin is definitely the way to go.
- ability to 'hot swap' reels of filament when one runs out - an annoyance on larger prints as the pause and swap method on the ender 3 is seriously hot and miss and can easily wreck a print.
CFS does this automatically *IF* the filament is the identical (brand, model and colour). Upon installing a reel, you tell the printer what filament it is and its colour. Or for RFID filaments, it reads it itself. In both cases, it can only do this *BEFORE* a print is started, not during. I use this all the time - if a spool is looking low, I chuck in another, so it can use up the empty one first, then change to the full one.
- multi filament printing - very very low level want. My son will think it's the coolest thing in the world for about 90s before carrying on with his day.
Do some research on K2 pooping, and the amount it generates. You will need to print either a poop bin or poop chute with bin. Plenty of models available, or design yourself. Be aware that as it changes filament, that causes a CF retraction and CFS feed (obviously), and several nozzle wipes (number seems to depend on how big a colour change), which do make a lot of noise.