There’s an internet archive. A really big one, too.
I wonder if there will be one day some job called „Web historian“ or so. A Web Historian had to specialize early in his studies, eg. on blogs of exactly 19 year old british female students with red hair, or passionate private websites on fantasy literature with a focus on dragons (without web-galleries), or even import/export websites selling pu’er tea cakes under 50€.
Fascinating.