Aside from what Almeuit said, no. They have to plan the network for X number of users using Y amount of data per second. Most data is either downloading files (which can be on a "you get a packet when there's space for one in the data stream" basis, so it's not smooth. (Do an Ookla speed test and you'll see the speed varying - that's because the file is being sent one packet at a time, and sometimes there's just no room to insert one for a "packet time" or two.) Video has to be on a steady stream basis, or you sit there watching the circle go around (buffering) until there's room for a packet - and, of course, you scream about it, right?
So no, you can't do whatever you want with data. If everyone got on there and streamed 1080p at the same time, everyone would be spending most of the time buffering. You can download emails, SMS, files, anything you like, but if you want to stream something, it has to be either a continuous stream or you're going to be an unhappy camper. (You just don't notice the jerky effect on file downloads, emails, etc., but it's there. You notice it on a stream.)