Unable to email anyone from my primary domain; thanks Google Mail and G Suite

> Is there a chance that someone on the same outgoing network as you is spamming heavily and you get also blamed because of it?

No. If you read beyond the title, you'll notice an interesting point that IP address itself is not actually blacklisted, it's the domain name that's blacklisted, and the likely cause is sending certain nightly log summaries to one's own Gmail address.

> I don’t doubt Google’s classification is buggy but there might be ways to route around these bugs.

So far, because it's the domain name that's acquired "the low reputation", the workaround is to use a secondary domain name, from the very same IP address, no less.

> It’s super annoying that these systems are so inscrutable.

Exactly. Apparently, they've introduced Google Postmaster Tools, but in order to get any sort of a useful information out of it, you're required to be sending an order of hundreds of emails daily. Who does that from their own personal domain name? (And into Gmail and G Suite, no less.)