Gwynne Shotwell already announced it won't launch until 1st quarter of next year at the earliest. I would take her word over Rand Simberg any day.
One of the big things that needs to happen with the Falcon Heavy is to complete the engine test stand in McGregor that will fire all 27 engines for a full mission burn simulation. There appears to be some construction going on that may get that to happen this summer, so I don't think this is something you can shrug off and suggest will never happen, but there certainly are some steps that must happen first before that launch goes off. The current hang-up doesn't appear to be getting engines built for other launches as the Hawthorn plant (from the same interview) is now producing about one full 9 engine rocket core each month, three of which are going to be used for the Falcon Heavy.
The lease on pad 39A at Cape Canaveral is also going to be used for the Falcon Heavy launch, but the upcoming flight is going to launch at Vandenberg instead for the initial test flight. Pad work on the Vandenberg launch site has been ongonig for a couple of years now in preparation for the Falcon Heavy. One of the problems with LC-40 is that the strongback lifter system is positioned in the wrong location to work with the Falcon Heavy in terms of having the flame trench positioned for all 27 engines properly and needs to be rotated 90 degrees, hence why the move for 39A. That is one of the things being worked on in Vandenberg.
I won't even touch the rest of the disparaging remarks you made here about SpaceX, but I will say that sometimes fans do get the best of themselves and are overly optimistic. I hope that is some actual analysis that shows some reasoning for some actual launch dates, and I'll even admit the launch could be pushed back another six months to another year even beyond next year. On the other hand, critical issues like getting the engines developed are already done and the other sub-systems are not really seen as significant critical path issues. The largest hang-up is the cross-feed system between the cores that may or may not even be fully implemented on the maiden flight.