Passive is ALWAYS possible, it's how big the heatsink needs to be and if it's capable of dissipating the heat in the space it's given is the issue... just look at the next mac pro, technically they're passively cooled as they don't have their own fan and rely on the case fans, which is basically how most current motherboard chipsets are cooled.
The thing is if I'm buying a new pc (and in my case I would be changing to amd from intel) I would be looking at 'future proofing' so I get as much life out of it as possible so at the moment at least that means x570. I do 3D etc so obviously I'd be picking the 16c/32t cpu
As I like to make 'upgrades' when I upgrade I'd also be going pcie4 m2 ssd's for the os and scratch disk as that seems like a natural progression from sata ssd's, cost allowing pcie4 seems the more obvious option and as you say they have more performance and as such run hotter so that's why I'm 'concerned' over the shields (which weren't that good on pcie3 ssds) on the m2 slots. The shield would block cooling to the ssd passive coolers, so I'm curious as to why some brands have made them so you can't even run without the shields... It's not like your average user is going to remove the standard ssd cooler for the motherboard one when it would in most cases void your warranty.