How do lava lamps help with encryption?

This has been discussed many times on HN, including as far back as 2017: https://news.ycombinator.com/item?id=34925320

The tldr is it's a cute marketing / interior design stunt by Cloudflare. The lamps certainly produce entropy, but you can get good randomness much cheaper and quicker from a Hardware Random Number Generator (HWRNG) that uses thermal noise or radioactive decay, which is what most people do.