Jamming is not a DoS attack. The essential feature of a DoS attack is that it forces the receiver to use resources, which it can then not attribute to legitimate users of the service. Jamming does not force a cell tower to use resources, hence it's not a DoS attack.

To put it another way, if jamming is a DoS attack, then so is hacking a server and reconfiguring its DNS. But we don't call that type of attack a DoS attack, we call it a penetration, or simply a hack.

And yes, wireless communications are susceptible to more physical attacks, such as jamming, but jamming is a) easy to track down, and hence dangerous to execute, b) expensive, you need to invest in special hardware to do it and c)surprisingly difficult to effectively execute in a radio environment like a cell network, which is generally quite adept at routing around things like jamming ( if you put your jammer between me and the antenna, my phone will in all likelihood simply find another antenna to connect to on the other side of me - with signal strength dropping as the square of the distance, your jammer is going to need to be BIG to jam me effectively).