List of all SharePoint active sites... in a list (modern)

Juan beat me to the option to write code to do this. Another way to do this - potentially - is to have an approval process based on a SharePoint list for all Teams/SharePoint sites (since every team creates a SharePoint site). This way you capture the request and you can add more details via new columns. Of course, if you don't have a controlled process, then the only options may be (a) script or (b) hubs.