If you need construction materials delivered, this can accommodate almost anything. However usually for things like a stack of drywall, you would order a truck with a crane - simply because it's quicker to unload. For personal use the answer is simply to get a trailer. Here a lot of gas stations rent trailers by the hour for a reasonable fee, so it's very easy.
RVs also fit into this category. Most of them are under 3.5t, so you just need a standard car license. Some larger B class variants (which I guess in the US would still be considered small) need a C license. Caravans (travel trailers) are designed to be ok to tow on a standard car license, but in some countries you need extra training. Larger RVs don't make much sense here, as you won't be able to go anywhere with them.
People who have boats either leave them docked, or have boats that fit on a trailer that can be towed by a standard car. Nothing special needed. Same for cars, just put them on a trailer and drive away. Professionals often use car carrier variants of the Mercedes Sprinter et al, which can carry one or two cars, and another towed behind.
The kei trucks aren't really a good replacement even for an S10 since so far as I can tell they won't run at highway speeds, but they're really good replacement for the Canam and Polaris money pits people buy (and are certainly way more capable of real work).
I don't own a truck anymore and now my "hack" is to remove the middle seats from my minivan and fold down the back row seats. That creates enough room that I can fit full 4'x8' sheets in it (with zero room to spare). I've hauled drywall and plywood in it with no problem. I sometimes get weird looks from folks when I roll up to the back of my minivan with a cart of plywood at the big box store.
Pretty sure the tiny bed on my grandfather's 1970 Datsun is larger than the beds on some of these behemoths.
Is it really dads? I've seen claims that is actually moms demanding this, dads just go along. (dads would be happy in a minivan, but their wife won't let their husbands be seen in one)
Pickup trucks don't need to be heavy. Japan has kei pickups, in the US, we had small pickups in the 80s and 90s. And then they disappeared throughout the early 00s.
A small truck with a small engine does small truck things, and has decent fuel economy and tremendous visibility.
But we can't buy those new anymore because you can't get a small truck to hit cafe standards, so large trucks it is.