Although I do NOT believe that a cell phone transmission is a danger, and the heating you are talking about is the LiIon battery; I use a blue tooth. First it is convenient, second, if I am wrong, the cell is on the table.
The towers are another question, as instead of and average of 0.1 watts output; They can go to 5 watts
https://www.mwrf.com/systems/5g-front-end-reference-design-meets-multiple-needs
The most reactive frequency is 2.4 Ghz, since this is the frequency that resonates water. Like a microwave oven (also set at 2.4 Ghz) a 5g output will excite water. That is where the comparison ends, because instead of the full 1100 watts of output through a focussed antenna into food in very close proximity; we have a donut shaped dispersal pattern, 100 feet above the ground, being driven by up to 5 watts. We get more EMI from local power lines than that. *I am not saying that NO physical affects are possible, as you have aptly stated, we do NOT yet know, but do NOT focus on one, and ignore the others!
My Father in Law ran the legal limit on Ham radio across most of the bands offered, for 60 years, and suffered no Ill effects from EMI radiation. I have run similar power for 30 + years on all bands including some in this frequency range, and am unaffected. So I guess I am a voluntary guinea pig for this testing, ROFLOL! So Study, but do NOT panic.
That said, I am VERY disturbed by what this Doctor did! OPEN DEBATE is critical to all progress! IF you are scared of another person's views; you should be re-examining your own views!