Thankfully; there are entire (completely-local) applications designed around MSHTML.
Invoke-WebRequest still depends on some of the internals too probably, but who knows?
That was finally fixed, apparently in PowerShell 6.0, and now -UseBasicParsing is just a noop. Kinda crazy that it ever did this by default, especially considering PowerShell used to alias curl to Invoke-Webrequest, which could lead to surprise JavaScript execution. Definitely one of the worst gotchas in Windows PowerShell.