LTE: why are high frequencies faster than low frequencies?

Lower frequency waves (e.g. B20/800 MHz) normally travel more easily through materials than higher frequency waves (e.g. B1/2100 MHz) as materials have lower attenuation coefficients for waves at these lower frequencies. LTE on Band 20 (800 MHz) can inherently transmit and receive across greater distances than LTE on Band 40 (2300 MHz), because of the general rule of higher frequencies have higher attenuation coefficients, meaning power loss is higher over longer distances. Bandwidth RBs Subcarriers 1.4 MHz 6 72 3 MHz 15 180 5 MHz 25 375 10 MHz 50 600 15 MHz 75 975 20 MHz 100 1200