Someone develops logseq which is completely foss and like obsidian. Now I can choose to donate to FOSS or buy closed source. How do you decide?

We just need to establish paying for open source software more.

https://github.com/logseq/logseq/

Iirc, the subsidy was ~7000€. When the subsidy ended, car prices dropped by roughly 5000€. Meaning, there was a gift for the manufacturers and nothing changed. Of course, you can't brag about your 40k car anymore because it's only 35k now. And other smaller effects like the ads are different now.