You realize your microwave operates at over 1100 watts in a small enclosure designed to reflect RF, while 5G currently maxes out at 1100 watts in an open space that dissipates the energy in all directions, right?
You also realize that a microwave is designed to use a frequency band that sympathetically excites hydrogen atoms, while 5G is a collection of technologies that use UHF, high microwave, and submillimeter bands that do not sympathetically excite hydrogen, right?
I agree.
Climbing to the top of a 5G antena while it is working and hugging will probably get you a few burns.
I also worked for some months with infrared and green laser that were powerful enough to cause eye damage. And if you want a less technological example, with a glass lens you can concentrate sunlight and burn many things.
The assorted things that have burned or exploded when I left them in my microwave oven too long suggest that this is not entirely correct.
Ionizing things is not the only mechanism by which radiation can cause harm. It's the only one known to be able to cause cancer, which seems to be the main thing people worry about, so it would be accurate to say non-ionizing radiation cannot cause cancer.
The non-ionizing ways radiation causes harm also tend to require high intensity and prolonged exposure, so it is probably accurate to say you don't have to worry about them unless you make a habit of, say, hanging out directly in front of high power microwave antennas.