Did I open this parenthetical?
I will try to keep this on topic though.
I just pointed out the difference in shocks. I am installing those on my 4Runner; they are not available for Subarus, nor is my 4Runner old.
As for lots of money on old vehicles to offroad them, this is kinda national sport around here. People would take a 1990s pickup and build what they call a pre-runner out of it. A prerunner is a vehicle used by desert race drivers to prerun a race course, most famously the Baja 1000. Of course, some just use another trophy truck (but each of those can cost 1 mln hence the utility of a prerunner). Most prerunner style vehicles are just built for the cool looks and don't cost nearly as much. But some people are serious about them. You can find youtube videos, big jumps and all.
A prerunner is built by installing a long travel suspension aiming at up to 20" up front and 30" of travel in the rear. So that's 50 cm front and 75 cm rear travel. The trophy trucks are normally 2WD, you don't need 4WD if you can carry enough speed. But to do that you need LOTS of wheel travel and extreme strength. For this reason, people spend 10-20-30-40,000 $ to turn a 5-10,000$ old truck into a capable race machine. So offroad capability on race vehicles derives first and above all from the suspension. Of course, you need a strong build, a powerful motor, and a good driver.
Here is one example:
These vehicles can be street legal in some states, like AZ, but they are said to be a real pain to drive on the road.
A second group of enthusiasts apply the same idea to rock crawling. This is even more popular in that there are places to practice in many more states. Serious folks will get an older low-end Wrangler and basically leave nothing but the frame and the body. Everything else, even motor and transmission may get replaced. So they bury tens of thousands of dollars into 10-30,000$ Wranglers. As with race trucks, so with rock crawlers suspensions alone cost 5 figures. Newer Wranglers cost more but you would not want a top of the line model if you will strip it completely. The video actually shows newer models but still gives you an idea of what the sport is like:
Here are 2 extreme trails that are 2 hours from my house:
A third group is the mud-trucks in the Southeast. I know nothing about this kind of offroading though.
A fourth way to throw lots and lots of money on toys is to buy a UTV. UTVs begin at around 20,000 for good sporty models.
To stay on topic, the common denominator between all four categories is suspension which is at the very heart of any vehicle from any of these four categories.
This is not true for the Australian 4x4 show that many watch on Youtube here, including myself on occasion. Suspensions on that show are used just to get the job done and the vehicles on the show are far too heavy to do any racing or serious by US standards rock crawling. Instead the focus is overlanding: getting to awesome places while having some fun "wheeling." In the US, the "wheeling" itself is the only goal for the 4 categories described above.
Here is an example of that, too:
Overland and sightseeing in the US is done by different people using different vehicles, usually mildly modified or, in some rare cases, built like Australian overland vehicles because they look cool even though that kind of build is not really necessary in the US (maybe in Alaska). The latter type of vehicle is generally associated with social media.
And finally an example of the social media offroading phenomenon: btw, I have driven that trail in my Outback.
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