Ideas for Data Sources

Switchlan traffic viewer
https://traffic.lan.switch.ch/ - educational in-depth data-access possible
https://traffic.lan.switch.ch/pub/graphs/

Publicly available traffic statistics of internet exchanges
https://www.swissix.ch/infrastructure/traffic
https://www.de-cix.net/en/locations/germany/frankfurt/statistics
https://stats.ams-ix.net/index.html
https://www.franceix.net/en/technical/traffic-statistics/
https://www.netnod.se/ix-stats/sums/All.html

Direct contact with these institutions would be needed to get access to computer readable data.
While these graphs show the aggregated traffic, especially flow based data would be interesting dig into the actual data (is IPTV growing? ...?)