The codecache WASM activity, is a JavaScript V8 problem. I am guessing that there may be a JavaScript V8 memory leak.
IIRC, There is a Brave Browser JavaScript V8 setting that can be disabled. Search for that setting and disable it.
Clear as much cache, cookies, etc as you can.
In the Brave Browser > Developer Tools > Network window, look around for the Disable Cache switch and enable that.
For testing, also disable all extensions.
Exit / Quit everything and Restart the computer. Test issue.
@Mattches - maybe a runaway JavaScript V8 issue with a burr under the V8 saddle. Meaning, JV8 is not the source of the issue, but very unsettled by whatever is the actual issue.