They very well might. Never underestimate the power of timing combined with marketing. It's what made the iPhone and countless other products.
I looked at the Dow and other systems, and they were quite expensive and not really wanting to talk to individual home owners, and when they did it was ridiculously obtuse and no installers would touch the things. They were 5 years too early and didn't have enough juice to make it happen, both likely inside of the company to essentially go all in, nor with public mind-share and installer credibility.
Cells are much cheaper now, home solar is much more of a known commodity, and you have a company with nation-wide installation presence fronting the install and handling all of that, and a man with free-press touting this. It definitely could have legs. If Musk does one thing well, it's identify things that are good ideas and feasible, but everyone is timid about, and then just take that idea and go balls-to-the-wall all out bet everything on it. Thus, he becomes a driving force, and every success adds to his confidence and ability to take massive bets and the cycle continues.