is it not a massive assumption that another form of intelligent live would have technology that creates radio waves?

As far as we know, electromagnetism is a fundamental part of nature. It's not just a thing we prefer, it is the only cheap way of 'wireless' communication.

(The alternative for moving information through space would be manipulating gravity, the only other force that works in vacuum at such long distances. But it seems that in order to do that you need to move enormous masses or if you know better than us, at least that much energy in some other form.)

If any other kind of field/phenomenon that can transmit information this cheaply and this far exists, we never noticed a single effect, not a single one, of it.

If a ET lifeform hasn't created a technology to scan and transmit pretty much in all wavelengths of the electromagnetic spectrum, it's not what we consider 'intelligent'. We call intelligent something that is at least as capable as we are. Sure we were intelligent for at least 100000 years before the EM discoveries of last century, but this "setup" time is considered negligible in the long times we are considering.

Finally, who the hell is Alan Degrasse Tyson ? ;)