That's not true actually, the software that powers wordpress.com is builtin and can power many sites from the same instance. https://codex.wordpress.org/Create

That's not true actually, the software that powers wordpress.com is builtin and can power many sites from the same instance. https://codex.wordpress.org/Create_A_Network https://codex.wordpress.org/Create_A_Network So while many hosters will offer a single instance (as it's more flexible), some, often companies doing it internally will use multisite just like wordpress.com.