I've filed two questions recently on unix stackexchange and for both I noticed that one of the tags I used
bash-script does not become an actual tag for the question.
bash-script is a synonym of the more general tag shell-script: you can use
bash-script as a tag name, but it's automatically rewritten to
shell-script. If you enter both, you'll only end up with shell-script.
Many questions about writing shell scripts don't depend on the exact shell being used, so shell-script is good enough. If your question is specifically about a bash feature, use shell-script and bash.