Yeh, Subarus etc. are all down with the small-is-good scene but they have a fraction of the ground clearance you might need to get up our local logging roads.
More importantly, a car (Subaru for example) is built on a unibody. That's a spot-welded sheetmetal box to which all the parts---engine frame, transmission carrier, etc.---are spot-welded. That construction is OK for going down the highway but it is not even close to durable enough for bumping along a logging road.
Even at very low speed the welds eventually become brittle if you roll the car over uneven surfaces a lot. Also, the many torsions on the unibody tweak it so over the unit's service life, things go out of whack, become misaligned, start to rattle.
One feature of most cars these days is front wheel drive. FWD is the primary drive system on any unibody car even if it has 4WD or AWD. Going off road is murder on FWD systems because they're built to take only highway bumps & stresses, no matter what the ads tell you. The parts are too lightweight. Year after year, late in the season, I roll slowly along the washboard up the Cascade River Road and am passed by FWD Hondas, Audis, Jettas, etc., all flying along at 30 mph. The drivers are fools, they're beating the crap out of their car's front suspensions/drive components.
The right vehicle for getting to our local trailheads is one built in the old-fashioned way, on a frame or chassis made of stout steel rails on which is bolted the body and all the other parts. That's a truck or an American car built no later than about the early 70's.
I drive a 2001 4WD Ranger with a limited slip differential and skid plates. I used to have an AWD Explorer but it was too heavy for its suspension and handled dangerously off road.
If I had to get rid of the Ranger, my 2nd choice would be a truck of any age. 3rd choice, if I had to drive a car to the trailhead, it'd be something like a '68 2-door or a station wagon. No way in hell would I ever rely on a unibody vehicle---a Subaru, any FWD car, or any of the truck-lookalike import SUVs which are all unibody-built.
It's right to be concerned with the impact your choice has on the immediate world right now but considering how much energy goes in to building a car/truck, you also need to consider how long it will last under the use you intend. A vehicle that makes the hippies happy now may last a fraction of its normal useful life if you use it in a way that ruins it. Beware of the car company ads.