I don't really think 222nm UVC LEDs are going to be super relevant anytime soon https://www.convergentresearch.org/resources/convergent/soli...
SHG chips might get there but they're very early days right now. And solid state capital economics are pretty unforgiving--I think we'd have to be seeing millions of lamp sales annually for SHG to really compete with KrCl lamps
Honestly, the KrCl lamps currently available are already pretty cheap even at the very small scale they're being sold. If demand picked up I think they could easily fall from $500/lamp to $100/lamp without any serious innovation.
It would be awesome if SHG could beat that and I think it has tons of advantages, but white LEDs got as cheap and efficient as fast as they did because literally everybody needs lightbulbs and they used to consume a lot of energy--general lighting is a huge industry with tons of demand. UVC simply is not.
I hadn't heard about the SHG platform. Thanks for the link!