“New home page seems like Stack Overflow doesn't allow free use any more”
First, it looks like the StackOverflow homepage was changed to not require a sign-in.  The heavily downvoted (about -50) answer[0] by Cesar M at the bottom of the page also shows the screenshot of the change.Second, I'm guessing that revenue from job postings (Careers section) and banner ads did not bring enough money.  From what I remember reading, I think SO also had high hopes of the other StackExchange specialty sites using the same Q&A engine would be more successful (i.e. more banner ads, more money, etc) but it turns out they were only a modest impact on revenue.  (E.g. MathOverflow is an interesting community with Fields Medal mathematics PhDs but it probably doesn't bring much revenue.)Therefore, this leaves the "enterprise sales" revenue idea of licensing the Q&A engine to private teams.  (Hey, Slack just had their IPO and some companies pay for Gitlab and Github -- so let's push for selling SO Q&A for enterprises.) This monetization pressure leads to using the SO landing page as a giant billboard for their enterprise product.  (I'm not making a personal complaint but just observing that they seem to be in a difficult monetization dilemma and their actions to improve their financial situation just irritates the users.)IMO, I'm skeptical that internal Q&A platforms would actually be useful for companies and I made a previous comment explaining why.[1][0] https://meta.stackoverflow.com/a/386566[1] https://news.ycombinator.com/item?id=14804834