If you look up that "professor" you will see him quoted saying for the same thing for UMTS (that's 3G...), and spouting non-sense on how he has developed some gizmo to detect "Electromagnetic Sensitive people". Yeah.
Also, spamming the thread with multiple unsubstantiated posts in the hope that one of them sticks is not at all the behaviour of a crank. The problem I have with this is that if at one point in the future there is indeed a health risk and skepticism is required, such position will be undermined by years of publishing/posting nonsense like these, where the same pseudo-scientific bullshit is repeated over and over for 2G, 3G, 4G, 5G, etc.
As a side note, I used to work in the telecom industry for a decade, sometimes having dozens of mobile phones tested in a day, and at some point using a test antenna. You can bet your ass that I kept myself informed with health risks and would have found something else to do had there been any doubt. So would have my colleagues, and so would have consultants that could have walked out on a dime. Like many people in that space I worked for an independent mid-sized company: to think that tens of thousands of people in that industry, scattered among many independent entities, would let themselves be exposed to radiation risks and that they would not say anything is just dumb.