I guess my take on it is there are as many different camper sizes and choices as there are potential owners with different needs. Some people pack light and/or do 7 - 10 day trips at the longest (my wife and I fall into this category) and a light weight, more overland-capable camper is of higher value due to the tight, tree branch prolific, narrow, rough forest service roads we frequent. Some live in their camper or do month long trips or simply want a lot of kitchen items, food, clothing with them even on short trips. For everything there is a trade off, but with so many camper choices, one can pick and choose how much storage vs the other trade offs of size (where you can fit), weight (related to how much pickup you need to haul it and all your supplies), convenience (pop top or hard sided), etc. You can get even lighter, more sparsely equipped campers or larger, better equipped campers and in the end, it's up to a potential owner to look at a particular camper's features and, if it isn't adequate for their use, determine if there are mods that can be done to accommodate your needs or cross it off the list.
We camp out of a CAMP-X on an double cab pickup (not crew cab) with the 2/3 rear seat removed and replaced with a homemade platform. We each carry our clothes in a duffle bag. Our kitchen supplies, non-fridge food, and our cookware/plates/cups (smaller, lighter weight camping-type gear) is all stored in bins that we store in a cabinet while driving and pull out and set on the countertops when the top is popped and camping. Most of our trips are 1 or 2 nights on the weekends with several 7 to 10 day trips per year. We are happy using our camper like this, but understand there are others that want everything to be in a permanent place, have large, fullsize pots and pans, big and/or numerous dishes and silverware, coffee makers, entire selection of spices, etc. I submit that those types of users would find most popup campers do not meet their space and carrying capacity needs and would be better served by a larger rig.
Camper shopping is fun and part of that is looking at different campers and thinking through where everything you take with you would go. Or maybe even considering if you are willing to change the way you pack as a trade off for other camper specs that you want. I've yet to run across a camper that is perfect for us and all our trips. We'd personally need at least two rigs for that (well insulated and quiet, huge hard side pickup camper or campervan for traditional cross country trips to national parks, trips that use campgrounds, deep winter camping, etc.) and a pop-top like we have now that can fit under the tree branches, handle the rough trail, is light weight, etc. Currently we have the latter because it is the only one of the two that will work for everything and we make due with it just fine on the longer road trips. It actually comes in handy because even the long road trip, national park types trips, we seek out regional dispersed camping to avoid the crowded campgrounds. We could not do that with a bigger rig and definitely could not use a hard sided camper or campervan on any of our weekend mountain trips/drives because it literally wouldn't fit under the tree branches or through the narrow trails.