Internet dies when downloading from Steam - eviltoast

I’ve had a weird issue with Steam lately.

Whenever I go to download a game on my pc, it will download fine, but I will lose internet for everything else on my network until the download is complete or I stop the download.

At first I thought this might be an issue with my ISP, but this doesn’t happen when downloading a game from my Steamdeck.

Anyone have any fixes for this?

Here is a speedtest if this helps at all: https://www.speedtest.net/result/15012239449