Certainly is not an issue with Brave alone, and certainly is not an issue with Windows 10 alone. Because, me and other users, are still able to use both without troubles.
It would be great to be able to identify what is actually causing this. Maybe more information about other potential SW would help. Extensions? Antivirus? Firewall? Installed versions (Win10 and Brave)? Graphical card? Brave configurations?
One well known configuration that affects performance in Win 10 is hardware acceleration. Try to deactivate it in Settings > System.
