It is ridiculous if cryptocurrency jobs are taking away a government's jobs. Governmental jobs and workers will be here to stay, there is no magic pixie dust that cryptocurrencies will be able to solve any meatspace problems. Both will co-exist in their own way, and those kinds of sector won't be hostile to compete with each other.
The main thing is, there is a significant difference between both sectors, so both will be distinguishable. As already been said, the direct threat would be the central bank, but still, I doubt it will lose its importance.
I agree, governmental jobs are a requirement for a government to continue existing. What crypto does is making sure that business' do not pay very low salary to people. I remember back in the day when I was doing my current job in the crypto field, but it was very early days and I was still looking for a 9-5 office job those days, and the offers were usually half of what I make here, and that's why I rejected them all, and even laughed at the face of few of them for their offer.
At the end of the day, I managed to make sure that this job is the best job I will ever have, and ever since that day, I have been so so so happy everyday that I have my job.