It’s easy to say you wouldn’t do that, but if it gets to the point where you have an employee helping you out and in a downturn you have to choose between laying them off or pushing an ad to keep paying them one more quarter, you might reconsider.

No, ads aren't the solution for everything, and in my opinion anything.

You will reconsider this argument when you start publishing your own ads to make people aware of your software.

there are different kinds of ads, but lets be clear that even a Show HN is a form of ad. Some forms of ads are just more appreciated than others.