And before you tell me that the GC isn't that big a deal: it is. Literally every big project I've worked on in a garbage collected language reserves a bunch of memory off-heap at startup and uses that for allocations on the critical path because the GC kills performance. You could replace occurrences of GC with malloc, switch the language to C, and it would be just as factual. Basically, what the author is saying is…
I argue that makes a language with has a GC that you can't avoid (as far as I know, it's impossible to allocate an 'object' off-heap in Go) a fairly poor choice for much system level work.
Which means, if Go is to find a niche, it's got to be at a 'higher-level.' And that requires competing more directly against Java or Python - a much higher bar than trying to be better than C.