> And yet the mainstream consensus is that C and JavaScript are terrible languages with deep design flaws.
Oh, they all have flaws. But whether these make them "terrible" is a matter of opinion. Because they are certainly all very much usable, useful and up to the tasks they were designed for, or they would have vanished a long time ago.
> and its proponents will finally be able to honestly accept and discuss its design flaws
We are already doing that.
But that doesn't mean we have to share anyones opinion on what is or isn't a terrible language, or their opinions about what languages we should use.
And yes, that is all these are: opinions. The only factually terrible languages are the ones noone uses, and not even all languages that vanished into obscurity are there because people thought them to be "terrible".
Go does a lot of things very well, is very convenient to use, solves a lot of very real problems, and has a lot to offer that is important and useful to us. That's why we use it. Opinions about which languages are supposedly "terrible" and which are not, is not enough to change that.
An new language has to demonstrate to us that its demands on our time are worth it. It doesn't matter if it implements the newest findings about how PLs should be designed according to someones opinion, it doesn't matter if its the bees knees and the shiniest new thing, it doesn't matter if it follows paradigm A and includes feature B...the only thing that matters is: "Are the advantages this new thing confers so important to us, that we have a net benefit from investing the time and effort to switch?"
If the answer to that question is "No", then coders won't switch, because they have no reason to do so. And to be very clear about something: The only person who can answer if that switch is worth for any given programmer, is that programmer.