They're actually doing the stuff they care about, i.e. their hobbies. The Gregs and Bryan Smith will continue their fantastic podcast and Greg Z will still write about the draft. They will not do the other, more daily and weekly writing that took up a lot of time in running a website like theirs. Makes sense they don't want to do that when they have or are expecting kids and wanting to spend time with their kids.
But you'd have to have read their writing to know that.