@keks yes, plugins-via-stdio does require us to come to an agreement now, about how those plugins are found and run. But your proposal of plugins-as-local-clients also requires us to come to an agreement now about how plugins connect and set them selves up.
I want to consider all the implications of the proposals: how they might be implemented, what limitations they have, how they may interact, etc. So if you say we don't need to agree about the plugin loader yet, well I still need to think about how that might work. I think the plugin loader is an integral part of the plugin system standard, by deferring that we just invite multiple incompatible plugin loaders.
hmm, I guess with plugins-as-clients you can just run a plugin in a terminal, or have a bash script that starts all the plugins sbot & plugin1 & plugin2
etc. Are these important features to you? It seems to me this might have some advantages during development. But I don't really understand why this appeals to you so much, aside from not needing to specify how a plugin loader works immediately.