You wrote that "Closed-source software" is unethical, not "harmful software & services" is unethical. There is a significant difference. Don't shift your goal as you like.
Not all closed-source software is harmful; Obsidian here is a prime example of one which is not harmful and could be even considered as beneficial, despite being closed source, because of how open and supportive it's designed in everything else.
I was just confirming the point you made -- the definition of ethical is not absolute, and there are people that consider questionable things ethical.
> Obsidian here is a prime example of one which is not harmful and could be even considered as beneficial, despite being closed source
All proprietary software is unethical. It's as simple as that. No matter whether it's free or paid, no matter whether it's useful or harmful. If you have a right to use it but are deprived of the right to alter it, it is not ethical.
Not all closed-source software is harmful; Obsidian here is a prime example of one which is not harmful and could be even considered as beneficial, despite being closed source, because of how open and supportive it's designed in everything else.