Heh, here you go: http://mxmap.be https://mxmap.ch/ https://kommune-epost-norge.netlify.app/ for Norway and https://swedish-mail-dependency.netlify.app/ for Sweden.

France even has an official map of this kind, with publicly visible recommendations: https://suiteterritoriale.anct.gouv.fr/conformite/cartograph...

Disclaimer: I made mxmap.be after seeing Swiss ant Dutch counterparts. I did not look at MX records only but also at EHLO replies, SPF and DMARC records and at fronting services.

In Belgium, 72% of the communes are on Microsoft 365:

https://jurgen.gaeremyn.be/2025/03/08/european-critical-depe...

"Purely based on the MX-records, we learn that 72% of Belgian municipalities run Microsoft mail servers and 60% of the Dutch municipalities. For Scandinavia, it’s 64% in Norway and 57% in Sweden. In Finland, it’s a whopping 77% if the cities that are being served by Microsoft."