In other words, Adobe products are providing high enough value that people don't find it feasible to move away from it. If it is pure network effect, we should be seeing a regular but increasing decline in their market share.
in other words: adobe has a monopoly. they can extract and do whatever they want to their users and nobody can do anything about it. same with apple. same with google. same with many other sv robber barons.
That's only part of it. There are plenty of Photoshop users who would prefer to switch but can't because of project constraints, or because it is a required format for some future step in the chain, or whatever. When you need no-hassle first-class support for PSD, or PDF, or that InDesign project that Mary from marketing sent you... who else can you turn to but Adobe?
You can't have the cake and eat it too.