Hi, I love Obsidian. It's part of my daily routine since a year or so, and I use it to store all my work and personal notes for the future. The main reason I use it is because of its note storage method. Instead of relying on a database, it utilizes plain text files written in Markdown, as most of you already know.
However, I have a strange feeling about it not being open source. The recent events with Reddit have only increased this discomfort. My notes are in plain Markdown, so I have the assurance that no one can forbid me from accessing them. I also take precautions by creating multiple backups, which provides additional security against virtual loss if I handle things correctly (which I do).
That being said, I would love to have alternatives like Joplin or LogSeq that adhere to the same philosophy of work as Obsidian.
Joplin is not suitable for me due to its reliance on database storage. I prefer to have total control over my notes.
On the other hand, LogSeq is more focused on serving as a diary rather than a personal knowledge manager, and it does not use pure markdown, wich will be a problem in the future when (not if) I'll need to migrate out of LogSeq.
I feel like a lot of the people that enjoy open source software tend to be able to read code in some capacity. Downloading visual studio code and the dendron extension is probably pretty easy for those folks. It's open source, checks most of the same boxes, and doesn't charge extra if you want to use it for work. I think I even saw some documentation detailing how to migrate from obsidian to dendron.
That being said, it really does feel like Obsidian is one of the more user friendly and intuitive options I've found. Maybe their business model is part of the reason why it is so feature rich and stable?