Assuming this system was in place 40 years ago “
Who says it was? I got married 34 years ago and was a child of the 60s, and it was not the norm for a typical frum chosson to take off a year or more to learn while his wife supported him, (though women had begun to enter the workforce in greater numbers). I am sure there were some, but not in the numbers that you see today.
Frum guys learned part of the day and worked the rest of the day, and more women than not still stayed home to raise their families, until women’s lib caught up with the frum world and “stay at home moms” became a pejorative expression. We have seen the dangers of kids being raised by non-Jewish babysitters, however wonderful they might be. It has reached a point where women sometimes feel that unless they are working at a “meaningful” job, their efforts are worthless. When did it become worthless to prepare the next generation of klal Yisroel? When did Hashem tell men to stop earning “b’zayas apecha” and turn that responsibility over to the women? Most of all, who is going to pick up the slack for the next generation, which are ILL-PREPARED for real achrayus in life. There is no money tree in my back yard, and even if there is one in yours, what happens when there is a drought and it stops producing? None of us lives forever and the last grouop of earning parents will eventually be gone. What then?