I had a quick try earlier with latest Chrome on Windows 10 (and Firefox) and I'm not getting any CORS errors in the debug console. I get just one error, which is for blocking
https://www.googletagmanager.com/gtag/js , but that's usually from (I think) the uBlock Origin plugin (and intentionally blocked).
I don't understand why you're getting the CORS errors and I'm not. I don't have anything funky customised in the browser and I suspect you don't either. It's almost like you have a super strict mode enabled somehow.
Maybe first try disabling plugins, especially adblockers?
I'm wondering whether your DNS provider could be causing this but I don't really see how.
[edit] - a good test may be to try through a VPN connection. A good free one I use is Windscribe (10GB free a month), though others are available obviously. There's a plugin/addon for Chrome for Windscribe which works well. This would bypass any possible blocking which your ISP may be providing.
[edit2] - possibly your HTTP requests are running through a proxy? Could it be an antivirus acting as a local proxy? I see you have the problem on several computers so maybe the same antivirus on both?