With a USD$7k price tag (excluding installation and inverters),...

With a USD$7k price tag (excluding installation and inverters), a max power output of 3 kW, and an 80% round trip efficiency, it just doesn’t look like a good fit for most on grid residential applications.
Those considerations are overruled though for off grid, fire conscious, recycle-minded, technically savvy consumers. Those aren’t the majority of residential consumers, though.
If you’re on a reliable grid like most residential consumers, you need the price tag to be down around $1-2k fully installed (including inverters) before it makes economic sense. And that’s a long way off.
So RFX are right to target who they’re targeting. We just need to accept the sales cycle into Telcos is very slow. I hope they break in before they go under.