That's what I did when I semi retired, cut account by 75% and quit using stops because I now only need consistent profits better than investing but not large profits like if I owned a business. There is no problem with trading. I won't say it's easy but quite doable if you stick with it. The problem arises when you need large monthly profits on an account that is so large that if you lost it all it would be a tragedy.
When you dollar average down, the subsequent move back can be a significant profit maker. Obviously, your position is no longer small. The portfolio risk is higher. But the terminal loss at zero is significantly less from the original trade. Then there is the assumption that the underlying business has a residual Value and that zero is highly unlikely but still possible.
That is where I've made the bulk of my profits over the last 30 years. My first trade was always the worst one. Total portfolio risk was approximately 10% at zero.