I would like to know if queries done to Salesforce through Salesforce data actions count toward Salesforce API limits:
I know that every API call that Purecloud for Salesforce does not impact these limits, but Salesforce data action is different (not part of a AppExchange package like Purecloud for Salesforce)
Yes, Data Actions would count against API limits. PureCloud for Salesforce is generally using the OpenCTI api, which is a different category of behavior than the standard REST API.