You could also start a browser with a completely blank profile, create a github account with that browser instance, trash the profile and continue with the CLI version.
Something like:
mkdir /tmp/ff-trash && firefox --profile /tmp/ff-trash --no-remote && rm -rf /tmp/ff-trash
There are ways for github to use browser fingerprinting and so on. But this would already reduce the amount of information given to them.
And I don’t know of any issue tracking system that does not require an account creation.