Slow download speeds from Google Drive (GSuite) mounted on desktop

Hello,

I am having a very weird problem, and after discussing at length with Google tech support, they have reviewed my logs and are blaming my ISP for potential throttling or rate limiting. So I am posting here in the hopes of getting a resolution.

I have a Google Drive account, and require the ability to download large files to my desktop. I have tried a variety of different apps to allow me to mount the Google Drive to my desktop and have it appear as a network mounted drive. These apps include Google Drive File Stream, Rclone mount, and NetDrive.

With all three solutions, I get an abysmally slow download speed whenever I try to copy anything from Google Drive to a local drive. The download speed seems to be capped at 3mpbs. My subscribed connection speed is 500mbps / 35mbps. So I certainly should be getting a faster download speed than 3mbps.

Now, here is what I think is proof that this problem lies with my ISP (Comcast). At the request of a coworker, I tried installing a VPN and running my traffic through the VPN. When I did so, the speed of the download increased drastically, to about 250mbps. I'm still not getting the full download speed, because some of the bandwidth is taken up by the VPN. But it does prove that there is something going on between the ISP and Google to throttle the speed from the Google Drive.

Has anyone experienced anything like this? Or better yet, can someone from Comcast help me out with this issue?

Thanks in advance...