Don't start a business unless it's a pain point you are personally invested in. Lifestyle-wise, it's a grind with mental health challenges along the way, as you pointed out. Salary-wise, it's unlikely that your own business will ever match a regular developer job. It took me 4 years of bootstrapping before I had a decent baseline salary, and it's still lower than my ML engineer salary 10 years ago.

I don't get the current culture of starting a business for the sake of starting a business. The lifestyle can be great after a few years when everything is running smoothly. But the marketing ignores the fact that it takes multiple years of grinding to get there, with no guarantees.

Specific to your situation, it sounds like you were reaching the wrong audience. You need to reach the audience interested in your product, not an audience of other entrepreneurs. This takes a lot of time and energy. Marketing needs to be more than 50% of your effort these days. Content marketing on social, blogs, and Youtube tends to do well, but takes a couple of years to ramp up.

Thanks for sharing, and I'm glad you made the right decision for you. Mental health is the most important asset you have - you're wise to protect it.