How these three relate

It helps to see these as three different diseases with three different cures:

• Context rot is a volume problem. The window is too full. The cure is reduction (compaction and summarization).
• Context pollution is a relevance problem. The window holds the wrong things. The cure is being selective about what enters and isolating work into separate contexts.
• Context confusion is a clarity problem. The instructions or tools clash. The cure is fewer, clearer tools and non-conflicting instructions.

The reason the articles bother to separate these is that the wrong cure does not help. Summarizing your history (a fix for rot) does nothing for a toolset that is too large (a confusion problem). Naming the failure points you at the right move.