I didn't see Fractal being mentioned. IIRX they have received some founding from Puri.sm recently. Sorry if I messed it as I didn't read the entire article.
The youtube video at the end shows an alternative C2S and S2S transport being used - similar to the one described at https://fosdem.org/2019/schedule/event/matrix/. Atm it's experimental and only works in closed networks and isn't yet released, but the plan is to add it as an official alt transport once we've got it working nicely in open networks. It's about 30-50x more bandwidth efficient than the default HTTP/1.1+TLS+JSON transport.