From what I gathered from the article, one of your problems is that you didn’t understand the economics before you launched, and therefore your pricing was disconnected from the true costs. Next time, try to anticipate these by breaking down the various input factors (material, machine wear, design time, desired profit margin, etc). You may get an answer that convinces you it’s not worth it before you invest time.
I way under-estimated how long it would take to actually design something. I did a cost breakdown ahead of time on printing time + materials, but at that time the designs were simple, just text.
As things advanced, we had people ask for logos, and recreating them is really what took time.
There is still one lever here, and that was to increase the price to make that design time actually worth it. If I had to continue, that's what I would have done, but I was still losing my weekends and my free time was just more valuable.