No sane person will simply want to put all their eggs into one basket and I am sure most of the people that invested earlier into cryptocurrency and have been able to get rich through that must have been able to find other avenues to invest their money, which apparently could have created more jobs and as far as I am concerned, that is absolutely a development economically.
There will still always be these things in place and it is not like every single person will just concentrate on acquiring bitcoin since it is not like you can end up acquiring it for free.
I believe we are forgetting that the real purpose of bitcoin was to become a digital currency, which in itself means that the things you worry about is the things bitcoin is trying to achieve. Back in the day bitcoin was suppose to be a currency and used for buying and selling instead of trading to make money. In these days people are buying bitcoin and selling to make money and that makes you wonder if bitcoin can sustain or even hurt the economy but the economy had all the time to prove its going good however it is not, bitcoin is here to solve that problem and give the control to people.
I have seen some of them make predictions like they are able to tell the future but by the end of day it was never what they predicted that happens. People are never going to abandon their jobs just because of Bitcoin and Bitcoin is not meant for everyone except for those who are investors.
Yes, those who quit their regular job for the reason of some other passive income generation, must be just the lazy ones and those people should not be considered for the measurement of how bitcoin is going to impact the economic development of one country.