Your comparison of the Model T to horses is flawed. It wasn't the first automobile, but rather the first automobile produced on a moving assembly line. In other words, Ford had found a method to make cars, previously expensive and unreliable, into a viable mass market product. It was an improvement on prior automotive manufacturing technology.
What you're missing is that the Model T wasn't competing with horses, considering that production automobiles had been around for decades. It was competing with more expensive, heavier, less user friendly automobiles. The Buick Model 10 cost more, weighed more, and was mechanically inferior with its exposed clutch and user-oiled valve train. It, too, never got sick and puked on the side of the road. The market wasn't "Horse vs Model T", just like it's not "broom vs Roomba" today.
I don't get why it matters that your friend is Filipino or that her relatives have maids. We all know that some people have live-in maids. The question is, at what price point can comparably utile cleaning robots come to market? There will come a time when it costs less to have a robot (and hire an uber to drive the kids) than to have a person doing the same job.
When the technology brings that price point to a competitive level, the business opportunity will be obvious and there will be more investment. And that investment will bring the price down even further due to broader scale and more research money. Just as has happened with cars.
I think anyone who says robot design and manufacture are not going to encounter the quantum leaps that have graced every other technology known to man, is suffering from a lack of imagination and an inability to examine history. Imagine a group of cavemen arguing that stone tools are cheaper and better and more accessible than bronze because metals are too complicated to dig up and refine, fire is hard to deal with, and as a result the accessible bronze tools of the era are defective and poorly forged. They have a point but they are wrong in the long term. Technology advances and becomes cheaper as people find clever new ways to tackle old problems.
Meanwhile, there are always a bunch of uncreative naysayers standing on the sidelines. Obviously, people who say "this idea will never, ever be viable" are not going to be the ones who innovate and make money. For every Thomas Edison, there are a thousand less productive engineers who get frustrated and say "let's just stick to candles and gas lamps."
> human labor is relatively cheap compared to half a million dollars of machine.
Ask a laid off factory worker what he thinks about this.