>Requiring every component to be behind a network call seems like overkill in nearly all cases

That’s what I was referring to, sorry for the inaccurate adjective.

Most people try to split a monolith in domains, move code as libraries, or stuff like that - but IMO you rarely avoid a shared space importing the subdomains, with blurry/leaky boundaries, and with ownership falling between the cracks.

Micro services predispose better to avoid that shared space, as there is less expectation of an orchestrating common space. But as you say the cost is ridiculous.

I think there’s an unfilled space for an architectural design that somehow enforces boundaries and avoids common spaces as strongly as microservices do, without the physical separation.

How about old fashioned interprocess communication? You can have separate codebases, written in different languages, with different responsibilities, running on the same computer. Way fewer moving parts than RPC over a network.