If you look at the number of hostnames as measured by https://news.netcraft.com/archives/2018/09/24/september-2018-web-server-survey.html https://news.netcraft.

If you look at the number of hostnames as measured by https://news.netcraft.com/archives/2018/09/24/september-2018-web-server-survey.html https://news.netcraft.com/archives/2018/09/24/september-2018... (switch to linear scale) it shows basically similar trends. The 75% boost in websites is entirely due to parked domains. As for why, I suspect it's caused by the flood of new TLDs.