The question is : Is this not a bit premature to leave your full-time job to focus on something that are not even properly regulated and technologically matured? Some people might argue that early adopters might gain the edge over their competition, if they enter early.
Would you risk a stable income from a full-time job, to gamble on a experiment that has not yet matured?
The Crypto currency scene is very hostile and competitive and whales can still manipulate the value of the currencies. The fiat system is stable and less volatile and has more users. <bigger market>
1. Bitcoin is still in its early stage so everyone has a fair advantage, might be different in the next 10 or 20 years. Some people hodl bitcoin, others trade, some receive it as means of payment for their services/products. Holders doesn't have to quit their full-time job to focus on bitcoin.
As far as traders are concerned it depends, if a trader is making more money trading than his regular job, then quitting full-time job and focusing on bitcoin is a viable option if he understands the risks, possibile lack of a steady income, lack of a full-time job security. I personally would prefer full-time job/part-time trading.
2. If you are passionate about bitcoin, believe in its technology and future potential then I think quitting your full-time job and starting your own bitcoin startup or being part of other bitcoin related startups is a good option.
3. Keeping your full-time time job and getting paid in BTC for your part-time services or products is the safest option.
4. Yeah, crypto space is hostile, competitive, and can be manipulated to some extent. If you quit your full-time time job and focus only on cryptos, it's somewhat a gamble, it might pay off, may not. A regular job and into bitcoin seems safe.