Yeah, if you take like 15 pills on one day or something stupid like that.
But unlike the risk of taking 15 vitamin d pills, literally all the potential of giving you skin cancer.
This doesn't mean you have to be stupid and never go outside at all because "oh my goodness it's going to give me cancer". It just means that installing UVB emitters in our fucking light bulbs is a bad idea, and if you have vitamin d deficiency you can take a pill every day.
Because of innovations in LED technology, the amount of electricity used for lighting is down drastically (www.bloomberg.com)