I don't want to have to spend another grand because a $200 SSD failed. In other laptops, I don't have to do that.
I'm not sure you're clear on the difference between a SoC, and a System on a Motherboard. In the case of the motherboard, you are absolutely correct. However SoC means System on a Chip. For any manufacturer, if you put all the components into one IC, I'm not seeing how you can reasonably "repair" a component that's on that die? It's necessary to replace SoCs. But yeah, if you have an SSD on a motherboard, you should be able to replace it.
What if your SSD fails because the usage? I'am happy to replace it with a new one. But in a M1 SoC, you can't.
The whole motherboard is useless.