Why Internet Options/Properties Default Security level = COMPLETE GARB

i can't even believe I'm only discovering this now, but am trying to eliminate some persistent settings related to what windows believe is default for my pc. for example

click Intranet , customize, any virtually every security vulnerability known to humans and AI alike are left enabled (except a few).. xss scripting, redirects, auto downloads, plugins for activeX, and before anyone says well that's supposed to be that way cause it's your private local network.

NO, SCREW that , this is a window 10 home pc, not a ****ing honey pot for Netflix, HBO , Java and xml to all gang bang each other in a brightly lit room while im teathered to a chair forced to watch .

saw this after setting up a non windows ,, non windows (local sign-in) standard account.. I'm certain I'm missing a shit ton here but **** if anyone discovers what it is today and certain it's changed by the time i kinda start to learn it. fml

HP mobile vintage Tank

10 Home 20H2 19042.804

Most of these settings are for IE only, just a tinny subset are shared with all browsers, and it varies from browser to browser.
Secondly these settings are configurable from specific browser, if not defaults are used from inetcpl.cpl

If you don't like defaults configure your browser for security, following link may help you to understand:
Securing Your Web Browser | CISA

This link is out of date for modern browsers but good start, so you need additional research.

Asking why is something default would be better directed to MS as only them know why.