VBScript, the syntax is aesthetically less pleasing, but there is no reason why it couldn't do anything that JavaScript can do, if more verbosely. (Of course, the semantics are inferior as well, but if VBScript had taken off, its semantics would likely have been improved at some point.)
Indeed, if we look at VBScript's cousin, VB.NET, we find both first order functions and async functions, at least in its newer versions.
(Keep in mind that those features weren't present in older versions of JavaScript either. Async functions were only added in ECMAScript 2016. First order functions have been there from the start, but ECMAScript 2015 greatly improved the syntax for anonymous functions with its introduction of arrow syntax.)
I'm genuinely terrified.
In VBScript that runs under Windows Script Host, callbacks are implemented using the WScript.ConnectObject method.
(I'm not sure about VBScript running under IE or classic ASP, if they could use the same method or had to use a different one. But anyway, if VBScript can do it in one context but not another, that would be a deficiency they could have easily fixed if there were a demand.)
Until, US anti-trust investigation and law suit against MS. Which hampered MS enough to open the web business to smaller competitors, like Google, Apple, etc.
The fact that Apple now completely owns iOS and is gatekeeper to mobile app store is ironic. And, Google owns online ad services and is gatekeeper to online ad space is also ironic.
https://thisdayintechhistory.com/05/26/bill-gates-internet-t...
to all the material discovered during US v. Microsoft, we know MS's plan was exactly what you said, after killing Netscape to avoid it becoming the new cross-OS runtime for apps.
Good point about MS leaving the Web fallow, which missed big opportunities Google and Apple (iPhone original app model was Web-only; native came almost a year later for games and for want of WebAssembly :-/).