Is it possible to get some blog stats via XML-RPC to some reporting tools?

I want to visualise some basic stats from my blog network (i.e. post counts per site in network, comments count etc.) in my BI reporting tool (actually a free Power BI Desktop from Microsoft). Is this possible? Can I get any stats / data via XML-RPC?

Since I am completely new to this subject then all I managed to do was to add https://www.onezeronull.com/xmlrpc.php as a report source to Power BI Desktop. But all it resulted was an error message saying:

Web.Contents method cannot read content from https://www.onezeronull.com/xmlrpc.php (405) Method Not Allowed

What am I missing?

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