The article specifically mentions field strength alone exceeding health recommendations. This can easily be measured and debunked. Other claims will be addressed separately.

Frequency makes a difference, by affecting penetration and energy level. Signal modulation leads to harmonics and/or pulsing fields, but saying that modulation matters is quite misleading as it is simply frequency and power variation.

(For 5G, the end-result should end up being less energy as reduced cell size leads to reduced broadcast power on both ends of the connection, dissipated entirely as heat in a lower volume of tissue as penetration depth has dropped - a net win)