Trying to understand Isolation/Transformers for modern SMPS in Car Amps

[Magicmastja]

Hello, so ive been trying to get a grasp on high power (1000W+) SMPS in car amps and I'm struggling to figure out how modern amps implement isolation. Im still new to the landscape of transformers, but from what I've gathered off shelf transformers seem to max out in the ballpark of 5-800W. I supposed that means most of the companies are doing custom-ordered units. Where I get confused is A when looking at reference designs for 500W+ amps it appears to be non-isolated configurations of PWM controllers running in parallel and B looking at some teardowns of high powered amps ill see a custom transformer but then also a high amperage rated inductor elsewhere in the power staging, which makes me ask a couple of questions:

1. Are all commercial manufactures isolating their designs? Might be a dumb question, I assumed yes for safety/legal reasons. But From what I've been trying to simulate with 2mhz controllers, GaN FETs, and premium inductors from the likes of Coilcraft and Vishay it seems feasible you could drive 12V 80A+ through an inductor with idk 85-90% efficiency?

2. If they are 100% isolating their designs, are there transformers able to handle 12V high current inputs? or are they breaking up the boost into 2+ stages to get the input current lower with high frequency controllers + inductors? I have heard push-pull setups were most common place but those info sources date back 8-15 years backwards so maybe things have changed.