I really don't want to critisize OP since building stuff for yourself is always a good mentality. But lets be realistic, 1000$ over 10 years is nothing. It will always cost more if you consider your own time for maintenance long term. Obsidian is one of the most consumer friendly business for note taking out of there, they are not VC so the Evernote comparison is unwarranted IMO.
I think the author point still stands though: Obsidian won’t probably be here in 20 years.
Even if Obsidian vanished tomorrow and the application became unmaintainable, I'd still have all my notes in a text based format.