I feel your pain. I went through the same sort of situation myself, though with happier results.
I moved from Florida to Canada 2 years ago, bringing our 2011 Volvo with us. We had bought the car new, it was pristine (Florida car), and turned over 50,000 miles on the drive up here. A few months later it was parked in our driveway when some guy (with his young daughter), who was driving too fast for the snowing conditions, spun out on his summer tires and hit the back corner of the Volvo, moving the car more than 4 feet. Another 6 inches and the car would have hit our other car that was parked beside it (good thing I had left a generous distance between).
So this was entirely not my fault (though I suppose my fault was I should have put a large boulder at the corner of my property to deflect such rougue vehicles, a number of people do that here). My car was entirely innocent. And I have video of him driving too fast, spinning and swerving right into our car (and bouncing back).
There was tremendous damage to my car, both body and mechanical. They essentially have some sort of "no fault" insurance here. In the end, my insurance paid out but I assume they got their money from the other driver's insurance.
The estimated repair cost was around the breakeven point. My insurance was really talking up that it might be "a loss". I was not keen to listen to this, My car had 54,000 miles on, it was pristine (a couple mechanics here were amazed that it was like new even on the underside...due to its life in Florida). I had put in a few thousand dollars in cash expenses shortly before this crash: factory engine block heater, winter snow tires, the "Out of Province" inspection for. registration (mandatory and this was several hundred $ right there).
I had planned to keep the another year or two until fully settled in in Canada. Buying a new/used car for a very large sum of cash was not in my fiscal plan for last year!
So I had set my guns that if the insurance was going to write off the car I would then make a claim on my homeowners insurance (same insurance company!) for the difference for what the repair would be. And I made that known, nicely. Several times.
In the end, the car has been repaired and beautifully so. Due to supply chain issues and also getting parts due to the age of the car, it took 10 months before I would get it back. I just got it back in February, no expense to me at all. The shop (that I had personally selected as they were low-volume and worked on boutique vehicles) did a fantastic job and the car is like new.
I did go through 2 months of stomach churning stress at the start with "what are they gonna do? and do I need to get a lawyer?".
I thoroughly understand having something "nice" and then someone else wrecks it and insurance just doesn't want to make you whole.
I have read of people whose really rare, high-end car, like an expensive Porsche, Lamborghini, etc, had body damage and the insurance had the car repaired, but the vehicle still had a diminished market value. Some people have sued in this case to recoup the monetary loss, I suppose from the other driver or insurance. In my case, I just wanted my nice clean Florida car fixed back to what it was. And I would wish the same for your car!
Perhaps you can sue the other driver and their insurance in small claims court for the difference in value between what insurance will give you for your car and what a comparable car truly sells for... to support this, check on-line for similar vehicles actually for sale. Check autotrader.com and similar sites for cars actually listed for sale, you can see cars located all over the US! You can even do this exercise before settling with your insurance.
A lesson that occurred to me some years back was that having anything out of the ordinary (such as a "nice" car due to low miles, or fancy, or an exotic Ferrari, etc) presents something of a risk. Risk due to unreimbursed damage, risk due the vehicle simply deteriorating due to age (why overspend on a car thinking that I'll keep it for many years when it starts deteriorating due to age in years even it has low miles; perhaps it's better to buy the lower cost car but trade more often? maybe someone can determine how to optimize this ownership? haha, that's something I would do.) Anyway, that is an interesting concept and one I keep in mind sometimes.
Good luck to you!