Fellow European here, we don't have kids but we were thinking at maybe getting a second dog, which made me look for a possible car replacement (we now have a 15+ year-old small hatchback). After some searching and calculating I found out that the "usefulness" of cars for my purported task (to transport two dogs in the back) can be summarized like this (in decreasing order): vans -> station wagons/estates -> SUVs/CUVs.
Unfortunately vans are on their out, I can't really understand the reason why (the VW Sharan will cease production this year, Ford C-Max ceased production back in 2019 etc), station wagons are also not feeling good, almost every car company is betting the house on SUVs/CUVs, which is a trend I don't like at all, because you get to pay more money for less utility.
A quick review https://www.youtube.com/watch?v=51fyxgcVrKM
S-Max vs. Forester Curb weight: 3626 lbs vs. 3620 Mileage: 44 mpg vs. 30 mpg Cargo: 77.69 cubic feet vs. 74.2 cubic feet
So about 6 pounds heavier and 4 cubic feet more space than the Forester. It would be interesting if we had a hybrid Forester to compare with, but that doesn't seem to exist (yet).
Also looked into U.S. vans being gas guzzlers. A comparable vehicle in the U.S. is the Toyota Sienna, since it's a hybrid minivan. It's 4700 pounds, gets 36 mpg (vs. 44 for S-Max), but has 101 cubic feet of cargo space, which is 1/3 more than the S-Max. Seems to correlate well with weight, which makes sense.
Based on this, my (current) take is that mid-size SUVs in the U.S. are equivalent to these smaller minivans elsewhere, and U.S. minivans are a bit larger and heavier than that.