Nobody is talking about invisibility. We're talking about total concealment and blindness, which is different. Again, even if you could use hearing to identify where someone is, there is nothing about hearing which identifies WHO someone is. And nothing to identify objects - like walls. You will still have to guess who is friend and who is foe, and where things are, no matter how you slice it.
I mean, you guys are literally arguing darkvision is mostly meaningless, that light sources are mostly meaningless, that everyone can see everything all the time just by hearing. That's not the rules as written. The rules don't make your hearing into radar. You still must be able to identify where a target is by normal logic and language. They don't need a rule for that - it's the friggen game that you have to say what you do where you do it!
Total Concealment, as a game term, no longer exists. Heavily Obscured is the 5e equivalent.
As for the rest, the rules are as [MENTION=6801209]mellored[/MENTION] presented them. As far as I can tell, Mearls nor Crawford have contradicted or further qualified them.
That isn't to say a DM would not be justified to require additional checks or decision points in certain circumstances. However, there are no official rules that dictate such measures.