Not all jurisdictions are the same; the UK is quite permissive, owners can fit almost anything provided it does not stick out and have sharp edges.
The Germans have it particularly hard, no TUV approval, you cannot legally fit it. Part of annual inspections is proving you have the approvals for any aftermarket alterations. It makes for beautiful kit but some scary prices.
(warning, i realized after i wrote my wall of text that i went down a rabbit hole... But this stuff interests me and in a former life i worked on some of this stuff)...
I really like that the US is generally leading with performance based regulations instead of technology and design regulations.
Once you own the car each state gets to determine which changes are tolerable and which are not. In my state, California, emissions changes are of a particular public interested which makes them tracked and only CARB (CA air resources board) approved equipment can be installed into vehicles.
At the federal level (which really isn't that involved in what happens after the vehicle is sold) they basically determine if the cost of the requiremen eclipse the public good. To make a tangible example, all new cars must have reverse cameras because the goverment has calculated that the benefit to the public in reducing back up accidents is larger than the cost of requiring the public to purchase the cameras. The performance standard are straight forward:
"The field of view must include a 10-foot by 20-foot zone directly behind the vehicle. The system must also meet other requirements including image size, linger time, response time, durability, and deactivation."
There is a bunch of recalls and consent orders in the industry right now because a couple of manufacturers cameras aren't starting up fast enough after the car enters reverse.
i know they studied the excess speed warning system like our grenadiers have but came to the conclusion that the economic benefit to the public was less than the cost imposed to the public by requiring these systems. That may change over time but this is what the analysis took them.
After the vehicle is sold you can modify it. Its up to your state to determine if that modification is allowed or not. most states doesn't care too much on wheter you put on bigger wheels or change bumpers. if you injure someone because of the modification, its a matter of liability which can be handled by the parties directly. This only changes when it becomes large enough of a concern for the population that the state has to regulate it. In CA there is an excess speed warning bill lingering in comittee to force the speed warning that ineos has onto all new cars.
Having said all of that, i expect there to be no major changes to vehicle regulations at the federal level in the next 4 years regardless who gets elected president. Biden will push the transportation secretary on aviation safety via FAA and Trump will revert back vehicle emissions standards to what he put in place when he was president. And that is all that will happen. I'm pretty happy about that because i like modifying my vehicles..
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However, so far I did not have any probs , not with the winch nor with the bumper. Using it frequently in the woods . 
