Jon, I did all my Master's notes will handrawn Mindmaps and had been using Buzan's approach for over a decade before.
I bought into MindManager for about 10 years but it palls in comparison to drafting a MM by hand.
That got expensive so I moved to FreeMind, stable v1.0.1 and bet2 2 v1.1.0, running under Java for nigh on universal.
In between I discovered TiddlyWikis and got hooked on Markdown and eventually found Obsidian.
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