The point is closed-source software needs official support because the developers are the only people with access to source code for maintenance. For open-source software, anybody with the knowledge can provide good support. Don't forget the point that open-source software are not developed by a single delegated team of developers in the first place, but by members from the public. So it seems natural that they be supported by the public as well.

And, evidence shows that patches for open-source OSes usually come even faster than that of closed-source ones.

Of course, for some "obstinate" enterprises that insist on buying expensive service contracts as an absolutely essential part of the procedure, then software without official support are not for them.