How does alcohol (sanitizer) kill viruses?
Alcohol is a solvent that can dissolve the plasma membrane of viruses and bacteria which is made from phospholipids. It can also denature proteins and further dissolve the contents of the virus.
When the membrane dissolves, the virus stops existing. In labs, our disinfecting alcohol sprays are 70:30 alcohol to water. The water helps the alcohol better dissolve and penetrate through the plasma membrane, so it makes it more effective.
On a related matter, the same principle applies to radio waves and is partly why microwave radio frequencies (WiFi at 2.4 or 5GHz; versus UV light 750 THz~30PHz) are disrupted by walls, where typical FM radio (100MHz) is not very affected at all (absent metal shielding which acts like an antenna.)
The other issue is that they are pushing so much data digitally using reliable methods, so that if a particular part of the message gets lost-in-transit, it has to resend the whole missing part (packet). With uni-directional (broadcast) or unreliable transmissions (missing data ignored and worked around like in streaming or gameplay), it just gets staticky (analog), pixelated (digitally, missing bits), or “jittery.”
A stronger emitter (more output) can penetrate deeper, but comes with problems; high output radio waves (like the microwave oven) or light sources can cause more substantial chemical changes than intended, breaking down the materials on surfaces (think sun-bleaching or cooking a potato), or healthy cells (eyes are especially vulnerable to high-output EM waves).
Finding the right frequency, delivering it accurately and consistently, with as little output as necessary for the given application (e.g, size of decontamination field, durability of infections materials, durability of surfaces, reflectivity) is a challenge of engineering.