If I were trying to convince myself to extract a (micro)service, today, I’d do it like this. First I’d have a conversation with myself:

I would reflect upon how most of the required acumen is operational and wonder if I’m trying to solve a design problem with operational complexity. If I still thought that operational complexity was worthwhile, I’d then reflect upon how close the code in question was to the necessary design. If it wasn’t, I would again kick the can down the road; if I can’t refactor the code when it’s objects and methods, there’s little hope I can refactor it once its spread across two codebases and interacting via network calls as API endpoints, clients, data formats, etc.

If, upon all that reflection, I was sure in my heart that I was ready to extract a service, it’d go something like this:

In short, I still don’t think service extraction is as awesome as it sounds on paper. But, if you can get to the point of making a Modular Monolith, and if you can level up your operations to deal with the demands of multiple services, you might successfully pull off (micro)services.