Both Java and Go are developed by mega corporations though. Hard to disentangle their successes from that. It's not hard to be successful (when success is measured as adoption) when you literally can't fail due to the giant pile and of never-ending cash and army of developers fueling your growth. Even if your language is terrible people will adopt it, if for no other reason than Google or Oracle are behind the project.

If Oracle were to disappear tomorrow I imagine Java would persist for quite a while as it's so embedded by now. It's the introductory language in schools across the US, so it's not going anywhere for now.

Go on the other hand I don't think would last very long (maybe a decade?) if Google decided to divorce themselves of the language, as it doesn't have the installed userbase of Java, but that's just my opinion. Who knows what would happen.