Where do you get stats on this info? Not refuting your claims but it's interesting data. I would've thought a wider gap in all biz to active websites since some countries run nearly all their biz on whatsapp/telegram/wechat.
I did count the number of ICANN domains on their zone files on czds and there are a few services selling pre compiled domain lists that do crawling for marketers (it is forbidden by ICANN to use zone files for marketing) I don't remember how I got the active website count of 100 to 150 million, maybe I interpolated by checking some ICANN domains or there's a domain list service that does it. Domain list services usually say how many domains are active regardless of whether they have a website or not
Of course parked domains add up to the active website count even though they have no relevant content