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.
Your data, being in Markdown format, is portable to anything that can handle the format so should Obsidian change its policies or make the app itself paid you're not SOL. But you will lose the functionality that Obsidian and its plugins provide, which could make that data less valuable to you in the short term. Nothing's perfect.
Right. Data is irreplaceable though, features and functionality can be re-implemented given enough motivation. Would it suck? Sure. But it beats having to write a scraper to save your stuff.