It's much more helpful to ask, "What would we lose if this company were broken up tomorrow into parts no larger than (say) the median company size?"

I guess such a big company is here because they managed to create a need. The question may be: "were we really worse off before we had what this company built?".

Example: if GitHub disappears tomorrow, that's likely a pretty big problem. But we were fine before GitHub, we just had different (not worse) workflows. GitHub created a dependency.