Browsers works slow when VPN is turned OFF (infinitely better when it's ON)

I am encountering a very, very strange issue.

I have a Dell XPS15 9530 with an i7, an RTX 4050, and 16GB of DDR5 RAM.

One day, while watching YouTube and doing nothing out of the ordinary, it crashed with the VIDEO_TDR_FAILURE error BSOD. After that, it booted back up with seemingly no issues, but the videos on YouTube kept playing at 144p and only for about 3 seconds before freezing. I noted that changing the browser does not help, and videos on other (non-YouTube) websites wouldn't work, either, regardless of whether the video itself is a YouTube embed or has a completely different source. Please note that videos "physically" on the computer (saved on my SSD) work perfectly fine with no issues. I've also loaded up a few games, and they work just fine, with no issues or performance drops. Other applications that require an internet connection (e.g., Discord, Steam) also work fine.

In short, only the browsers are acting up and working slowly; the computer seems fine otherwise.

Non-exhaustive list of websites that are experiencing issues:

• YouTube
• DeepL translator
• Google Translate
• ChatGPT
• Explain Everything (platform for professors to publish videos for students to watch)

These have been accessed by both Google and Edge, so merely changing the browser does not help.

Stuff I've done between then and now:

• Restarted the system (many, many times)
• Reinstalled and clean installed graphics drivers for both Nvidia and Intel
• Ran both quick full system checks by both SupportAssist (Dell's proprietary software) and Windows
• Ran a virus check by both Windows and Avast (free)
• Reinstalled the current version of Windows via Settings -> System -> Recovery -> Reinstall now
• Verified internet speeds via Ookla speedtest.
• Reinstalled Chrome
• Disabled and enabled hardware acceleration in Chrome
• Disabled and enabled JavaScript
• Disabled, uninstalled, and reinstalled all Chrome plugins
• Put Chrome out of efficiency mode
• Checked every driver and key program (like the browsers and Dell programs) for updates
• Checked Windows for updates

Please note that the reason I'm using a lot of the Dell programs is that when trying to update Intel drivers, the Intel website has directed me to use Dell's version of the software rather than Intel's because Dell may have modified drivers to work best with their machines (or something of that sort).

After all of that, the issue still wasn't fixed.

I then accidentally enabled my VPN (ZenMate) and... It worked! The videos are playing almost as normal now! A little slower than before this mess started, but at normal speeds for using the VPN.

Problem is, this is a hotfix. I am trying to find a permanent solution and find the cause of the behavior described above. Any help is appreciated!

Thank you in advance,

A terrified college student.