This band is not useful for long haul carriage due to atmospheric water vapor absorption. According to this chart, absorption between 200 and 280 GHz varies between 3 and 40 dB/km. That means at the low end only 50% of your signal is absorbed every km. At the high end, only 1/10,000th of your signal remains after each km.
this post speaks to similar issues including refraction.
That has not and will NEVER stop $TELCO from selling services across this with "UP TO" marketingspeak which means "we fuck you royally for a service which is online but effectively unuseable".