The problem with your suggested strategy is that societies that follow it are headed for evolution's recycle bin, to be replaced by societies that don't.
But of course, it seems that only the poor people want to reproduce anyway.
And as you say, affluent people typically behave as though they don't want to reproduce anyway. In some cases that's actual lack of desire, and in others it's because by the time they finish climbing academic and career ladders and jumping through all the hoops, they're too old, but the end result is the same.
This is only going to get worse as everything moves from manual labor to software. We will need more and more developers and less janitors, less cashiers, etc.
In 50 years there will be very few unskilled jobs. And they'll probably be something stupid like clicking ads or filling out surveys full time.
True, but there's an interesting twist. As more people are hired to write software and build computers, some of those people create robots, the robots take over more of the unskilled jobs, which further accelerates the process.
The middle class is GONE, and the lower class has grown immensely. So as a proportion, sure, they reproduce more. But that's just because we've grown so many of them.