Why would it be completely ridiculous? That's the end goal.
Its ridiculous because its going way-backwards in security, there would be no point in a strong encryption if all a hacker or thief has to do is find the backdoor. I mean it would be pretty hard to enforce it to begin with since you'd have to be the target of a legal investigation to begin with, as internet providers are not legally allow to look at the data moving thru their system due to privacy laws.
If they allow that to happen we'd pretty much be couple of steps closer to being the next China/UAE when it comes to the internet. It would do far more harm than good.
I know most businesses and corporations and just bout anyone dealing with commerce or sensitive material is going to be opposed to this. Almost like why spend extra money on a security firm when they're going to be easily bypassed with a backdoor, like I said I don't trust the government/ISP to keep information bout said 'backdoor' under wraps. One of those easier said than done deals.