So sort of: the 3g is part of a standard for data rates, but the difficulty, comes in that networks are not homogeneous. Similarly to how you might be familiar with 5Ghz and 2.4Ghz WiFi signals. As a general rule of thumb the higher the frequency the more data you can send but with more attenuation so the signal can be blocked more easily and cannot travel as far, whereas the inverse is true for lower frequencies. So while the generations did make some changes in terms of protocols— it also came with higher frequency emitters which can theoretically carry more data. Other changes include MIMO antennas which do beam forming to make more of the energy go in the direction of a user using constructive and destructive interference from an array of antennas to accomplish this. However marketing people are always very eager to adopt technical terms and inflate them into oblivion. However some of this can be attributed to honest misunderstanding within a company.

generation for cellular data, not wifi. I liked this video that explains it