I agree perfectly. It seems there are zillions of apps (just look at this thread), but the moment I look for my requirements (markdown, good math rendering, no format lockdown, decent GUI, basic backup options) it seems that no matter how I look the only options are Obsidian and Joplin. Joplin being open source, albeit not perfect, it is my choice.
It always surprises me how many apps there and how I don't get a feeling with 95% of them.