Implement -IncludeSuppressions parameter by rjmholt · Pull Request #1701 · PowerShell/PSScriptAnalyzer

Hmm, didn't realize -SuppressedOnly was an already existing parameter.
But I think we could still have the -IncludeSuppressions switch side by side with it but instead have some early validation logic to disallows the usage of both switches and throw an error (yes, this would be at runtime unfortunately). To me, multiple param sets for different switches not only make the code more complex but are also unintuitive as a user when I try to do tab completion and might not even be aware of other params that are excluded just because I chose to use one param and therefore don't know in most cases that this unintentional action is limiting what tab completion shows. Also, in case one person actually reads the docs and uses both switches, PowerShell's generic error is not helpful to users and although users could look at the cmdlet syntax block and try to understand what the param sets are, the reality is that most users don't understand it or just end up being frustrated by the time it takes them to figure out how to call the command.

Having said that, this topic is opinionated and I am sure the other side will argue for param sets with its early validation before actually running the command. Therefore I suggest we let a 3rd person like @JamesWTruher decide on this matter. I am happy with the rest of the PR.