I have had multiple events when I am using Brave to download files, that all my other apps which require internet connections cease working. Other browsers, mail, LASTPASS, Speedtest - none will do anything until my Brave download is complete and I restart my mac.
I expect the downloads to go on in the background while I work on other apps…
I’m very sorry for your poor experience, but Brave shouldn’t have the ability to interrupt the network activity of any other app on your device. I would suggest looking inot this more, as there may be something else causing the issue. I would suggest starting with your router; if you can, try connecting to another Wi-Fi hotspot (or tethering to your phone, if you have that ability).