@gc What about reliability? Data centres tend to have much more reliable power supplies and internet connections than domestic premises.
Additionally, sharing a large server with a bunch of others is greener than everyone running a tired old shitbox at home.
There's also a privacy implication - if you home host, you're exposing your home IP, which can give away personal location data. You can hide behind eg. CloudFlare, but at that point you may as well use a VPS or cloud instance.