the backdoor could be in the hardware - the logical conclusion of your position is that we should all fabricate our own computers from scratch so that we're sure that they're secure.
This is clearly a straw man, no one wants to do this, or is suggesting that we do this. But at some point, even the most hardened OSS advocate has to trust someone (usually the hardware manufacturer). You cannot verify that the device you're on doesn't spy on you, you have to rely on the manufacturer's word that it doesn't. And the manufacturer's suppliers, of course, because the manufacturer is trusting them.
Somewhere along the stack, we all have to draw a line and say "beyond this point, I trust that I am not being spied on". You choose to draw that line at the hardware point. Others choose to draw the line at the software point.
This is clearly a straw man, no one wants to do this, or is suggesting that we do this. But at some point, even the most hardened OSS advocate has to trust someone (usually the hardware manufacturer). You cannot verify that the device you're on doesn't spy on you, you have to rely on the manufacturer's word that it doesn't. And the manufacturer's suppliers, of course, because the manufacturer is trusting them.
Somewhere along the stack, we all have to draw a line and say "beyond this point, I trust that I am not being spied on". You choose to draw that line at the hardware point. Others choose to draw the line at the software point.