Alt-F4 is WIDELY known. You are correct, though, that Ctrl-F4 isn't as widely known. That said, Ctrl-W isn't as widely known either. They are standard, but so is Alt-F4/Ctrl-F4. Standard doesn't mean widely known or used. Just look at the number of people who don't know Ctrl-C/Ctrl-V/Ctrl-X, or even Ctrl-P/Ctrl-O/Ctrl-S. Those are very widely known and are definitely standards and yet many still don't know them.
And where does your INSERT comment come from? What's that have to do with the rest? In any case, there are times with INSERT is actually more useful for pasting depending on the app being used and what you're doing at the time. But, yes, it's not used much anymore.
As for the $beta thing you said... the OP wasn't asking how to get a $true/$false from it. The OP was saying that he thought the result of $beta in a beta would be $true rather than betaNN. The answer to the OP is that it is never $true and that it will always show the beta number if it's a beta. Obviously, you can convert betaNN to $true, but that's not what was asked. And I'm sure the OP knows that it's $true if it isn't false/0/null.