I installed Avast on my M1 Macbook Pro as it seems to be the only AV packages that are optimized for the M1. A day after install, I found that download or streaming speed on various sites were at a crawl. I checked the same sites from a Windows laptop and there was no problem. Wondering if it might be Avast, I uninstalled it and poof, download speeds back to normal. Very disappointing that Avast would magically cause that.