I seem to remember my dad paying $79.95 each in 1970 for three Royce-Union ten speeds from Gemco. These were steel rimmed low end bikes, but they were decent. Took a bit of fiddling to keep them going, but nothing ever broke badly.
I don't know what that works out to in todays dollars, but I'll bet that even the most expensive bike from Walmart or Target are way below this.
There's a minimum amount that you can pay for quality. The $85 mountain bike is just not going to hold up. Wobbly rims are acceptable on a coaster brake equipped cruiser, but not on a bike with rim brakes.
Wish that the single mommy of 4 could get decent bikes for $69.95. Wanting & deserving it don't mean it's going to happen.