My brother's new high rise apartment doesn't allow individual internet services

Honestly, what's stopping a high rise building from doing an internal GPON/XGS-PON distribution to all the buildings inside?

Get a mobile hotspot. I've been using one (Verizon) practically as my only internet provider for a while now. 5G up and down speeds are totally acceptable for everything I do. And there's nothing an apartment complex can do about it. You can also share your phone's internet with other devices. Obviously the real answer is to not live there! But if you must, it's not an internet death sentence.

Rev sharing agreements can be quite lucrative for the building owner.

Here's an old example https://www.biggerpockets.com/forums/432/topics/554933-cable...

Amazingly, those are advertised as "included amenities", as if they were a good thing. I'm sure a large number of people are fine with the idea of a managed internet - or they just don't understand.