At my work, we have a system about that large. We have about 50 or so capabilities/domains. Some of the bigger ones, like Orders or Quoting have 100s of service

At my work, we have a system about that large. We have about 50 or so capabilities/domains. Some of the bigger ones, like Orders or Quoting have 100s of services. Some may only have a few dozen. Many of these capabilities have their own “gateway” that defines an API for inter-capability communication. Many of the modern features rely heavily on async messages and consumers that process those messages and events. Some of these capabilities already existed as modules in a monolith desktop application from the 90s that has 1000s of “screens”.