What I've found is that regulations make it impossible to sell simple machines, labor costs make it impossible to compete on price, lawyers make it impossible to go to market without being sued, and consumers who say they want reliable, well-made goods will balk and buy cheap stuff en masse when it comes down to the wire. And that's if you actually succeed in designing and manufacturing a good product.
Someone could do it, I think. But I'm deterred by all the stuff I just wrote, and the people who succeed in businesses that seriously challenge the status quo are the ones aren't deterred by that stuff. And for every one guy who does succeed in pressuring the status quo, a hundred guys flame out... but again, guys who succeed aren't deterred by that either!