Google after two years of launching the beta version of the new Google Search Console and opening that beta up a year ago, Google has finally removed access to the old Google Search Console. There are still ways to get to some of the legacy reports but you can no longer access the main old dashboard anymore.
Here is a screen shot of the old dashboard:
Now, you can access the legacy reports for now in the new version under the "legacy tools and reports" section, here is a screen shot:
I believe Google launched webmaster tools, its former name prior to May 2015, in 2006. I cannot find the announcement blog post about it going live. In early 2005, Google began emailing webmasters about penalties - but this was prior to the manual actions section in Google Webmaster Tools - that came much later.
Vanessa Fox, former Googler, is credited as having created the original Google Webmaster Tools.
Here are some tweets from John Mueller of Google clarifying any confusion:
No. Just because it's still tied to the old Search Console doesn't mean you can't use it. Keep on disavowing (or not, whatever you prefer, of course :-))
— 🍌 John 🍌 (@JohnMu) September 9, 2019
No, no, nothing will replace Search Console (at least as far as I know..), it's just that we've been moving it to the new setup, and now it's getting time to slowly let go of the old one :).
— 🍌 John 🍌 (@JohnMu) September 10, 2019
In any event - this change should come as no surprise to anyone. Google has done this as slowly as almost any other launch I've seen.
Forum discussion at WebmasterWorld and Twitter.