2. his argument for moving away from MS GitHub is based on the understanding that license enforcement is lax in the modern era. the reasons he can expect to have greater license enforcement on a VPS than on MS GitHub may be real, but aren't immediately obvious to me. the most bulletproof defense seems to be one of obscurity: it takes a VPS provider more effort to decode his git repos than it does a managed git provider. any other defense i can come up with for why a VPS would enforce data agreements ought to apply similarly to GitHub (which is evidently not true).
i admit that a VPS achieves certain things better than self-hosting (as you say, it's easy to migrate, or deploy to multiple machines and have failover/load-balancing, etc). if the author is making a tradeoff between that and his license ideals, then his current solution might very well be right for him. on the other hand, if he prioritizes his license ideals as much as his post makes it seem, then he's already done half the work to go full self-hosting and may as well take the next step (as he says, "one day is worth it for a project that's going to have 10,000 hours of investment").
ownership is thorny (as the author is discovering). how does this change if you co-locate your box on the property of an internet exchange not owned by you? how does it change if you maintain physical possession of the host but there's some lien on it (i've never heard of somebody mortgaging a server, but there's no reason you couldn't)? i'm not sure. i think the concepts which "self-host" acts to label necessarily lie on a scale. if i were to attempt a strict boundary to which everything on one side is "self-hosting" and the other is not, there'd sure to be some contradictions. but i think at least notional ownership of the host is necessary for self-hosting and no VPS claims that.