Like I said, I don't necessarily agree with the idea and I don't feel strongly enough about it to really argue in its favor, but to answer the question: the same reason why OpenAI doesn't operate out of Sam Altman's garage.

At a certain level of compute you need specialized infrastructure -- such as a purpose-built datacenter -- for the energy needs (and really, I think the stronger argument to be made here is about energy, not raw speed, and where the argument might fall apart is the historical fact that compute tends to become more energy-efficient over time).

Not sure whether the breathing/murder analogy is apt, but I get where you're coming from and I would probably agree that a blanket restriction on computer speed wouldn't be appropriate.