The reason is that 10,000/year climb Hood. Stupid shit happens everywhere at some frequency. And BTW, there is no evidence that the climbers involved in this current incident did anything stupid. Rockfall/icefall can catch anybody despite gear/experience/weather forecast, especially on a shitpile rimefest of a mountain like Hood. It's way too early to even try to point any fingers at this point.
You are free to carry whatever gear/beacon/etc you deem necessary.
You are also free to state your case that climbers should individually make the decision to purchase/carry beacons/helmets/tutus/whatever... HOWEVER, I have a big problem with a climber publicly espousing legislating required behavior/gear. The media have quoted people from this website before and they will do it again. We have enough regs as it is.
Let's not give them the fodder to say, "many climbers support this legislation".
THIS is the message that climbers should be giving to the media