Account size to trade full time?

Yes, a micro account is a way to go for any beginner and add up as you gain more experience.
Yes slow progress is essential because newbies are likely to be emotionally unprepared to handle large loss this can push them out of balance and lead to careless gamble-like trading.
It’s about trading strategy too. Someone can come up with a good strategy but it will require a lot of time waiting to get profits. Meaning that it is appropriate mostly for higher timeframes.

This way you won’t be too sustainable as a full-time trader because you have to have money for your everyday needs. And not everybody can perform reliable scalping strategies. Not necessarily because of the professionalism, but because of the personality traits and temperament.
So the perfect amount for becoming a full-time trade is an open question without a one-size-fits-all solution as far as I can see it.
I like this question since I was asking myself the same question a long time ago. I couldn’t find an answer to it and decided to do it my way. After spending a couple of months trading with a small account size and trading with 0.1 or 0.2 lots, I realised that once I reached a level to trade comfortably with 1 standard lot, it would be enough to make decent monthly or weekly earnings.
So I put this as my goal. Building my account size to a level where I could afford to execute trades with 1 lot.
I gave you my example, however, you should know that this is a pretty subjective question that depends on many factors, such as your trading goal, your trading account size, your preferred instruments for trading etc.
The ideal account size to trade full time depends on your trading style, risk tolerance, and cost of living. Generally, having a substantial account, often in the six figures, provides a buffer for potential losses and supports a sustainable income. My working capital at Hotforex is 10-15K, with monthly profit target 1K USD