Depends how reliable you need.

I average probably a single 5 minute hiccup each month. That's 99.988% uptime. For someone wanting to run their WoW guild's voice chat server, or just a toy server, or a development/staging environment, that's plenty.

But I mean, my home internet is only 35 mbps anyways via Frontier FIOS. I can get 150 mbps through Comcast, but I refuse to give that company a penny of my money. In either case, I'm not going to be running any major production servers at home anyways.

I have Time Warner, and experience about 10-15 minutes of downtime a week on my home wifi and once a year it'll go down for an entire evening. That's annoying, but fine for home wifi and maybe a hobby website, but you couldn't run a company like that.

This is not at all true for me at least. I get very reliable internet, both at home and at my office. At my office I have static IPs and am allowed to host stuff..

Now I would not host my main customer site there. But dev servers? Beta servers? QA servers? Hey why not.. save some massive bills.

Exactly... you won't host a main customer site at home. If ISPs were smarter, they would make this easier for you and provide the tools to make it extremely easy. ISPs could have been AWS or Azure, instead they preferred to be a flaky bundle of wires.