Google Real Time Communications product lead Scott Johnston confirmed on Twitter, however, that this is untrue. According to Johnston, Google has made no decision to shut down Hangouts. Instead, Hangouts users will be transitioned to Hangouts Chat and Hangouts Meet.
Since then, 9to5Google has updated its original story with Johnston's quote. However, they also checked with a second source, who also corroborated the original story that Google will indeed be shutting down Hangouts by 2020 and that the decision has already been made.
Only time will tell who among them is telling the truth but for now we choose to go with Johnston's version.
However, even if we go by Johnston's explanation of transitioning users to Chat and Meet, it still means Hangouts as we know it today will cease to exist. Also, Chat and Meet are both enterprise-focused services that require G Suite accounts. How regular Google account holders using Hangouts will be transitioned to Chat and Meet also remains to be seen.
But regardless of the process, it is for certain Hangouts as it currently exists won't be around for much longer. None of the current users would care much for Chat and Meet functionalities and would rather have it keep working as it does now.
Google at this point has just gotten in the habit of shutting down services as soon as their popularity falls below the company's expectations, regardless of the people still using it. Some other examples such as Inbox and Reader come to mind. The company has also abandoned Allo, which means it won't have a messaging platform equal to Hangouts once it shuts down, unless they come up with yet another messaging platform, which knowing Google could happen any time.
I just wish the company settled on one particular service for messaging instead of starting from scratch every few years. Then again, at this point its probably too late, as people have already made their choice between Facebook Messenger, WhatsApp, WeChat, Telegram or iMessage.