I disagree. While they try to build backdoors its not that simple. Even if you have backdoor to every laptop in the world, its not an easy thing to smuggle out lots of data without people noticing.

We know from Snowden that they do not have backdoors into everything.

Its about economics, if they can listen in on the exchange its essentially free. If they have to backdoor every end user device, its gone cost a literal shit ton of money.