Well, yeah that's kind of my point. The best way for the president to directly reach people is through these tech companies. That's how powerful they've become. What's the alternative for direct communication?
Obama is just one president in a sea of 45 presidents over the course of 231 years. They all managed just fine without tech companies, and Trump will manage to find a way.
Besides whitehouse.gov, which he should've been using, he has no other way to quickly, directly communicate to any constituent that wants to see his message.
Oh wait...
It's ridiculous that people are actually trying to argue that the leader of the most powerful nation on Earth has no effective way to communicate with the public outside of Twitter.