Projects like Hestiia and Qarnot tried this in France years ago, using embedded computers as radiators. The idea isn't new, and it consistently runs into the same wall: security, reliability, and operational cost at scale. As others like @8jef mentioned, giving unknown individuals access to infrastructure brings unacceptable risks. Managing a fleet spread across basements means a massive, costly field ops team for servicing. Even with individual ownership, like Storj or Sia, the economic incentives rarely outweigh the risks and operational overhead for the average homeowner.

Nobody wants their home IP blocked because a neighbor's basement rack was compromised, let alone the liability for hardware or data breaches on their property. It just doesn't pencil out.