You’d be surprised. Check AliExpress. There are aftermarket units built to fit perfectly into every dumb auto fascia they’ve come up with to prevent it. A simple harness adapted is usually sufficient to restore steering wheel controls etc.
I’ve heard of a couple of vehicles where you simply cannot replace the media centre because it doubles as climate control input etc but the simple answer is: refuse to buy those vehicles.
I keep looking at maps and wondering how Ukraine haven’t been routed and cut off in enemy territory with no supply lines. What they’re doing seems borderline insane but more power to them!