Disruption typically happens where it's not only more efficient but cheaper too. The number of people you displace is going to be a fraction of what you make.
If you do end up making as much as the original industry it's because you are doing MORE than the original industry in which case you now have to question if the original industry didn't deserve to be destroyed.
Everything that can be software, will be software, what needs to happen is that the number of things that are software needs to outnumber the things that exist now. Software will create work for people to do as long as it keeps pushing what we can do as people. People need to adapt to a world with software at the heart, everything else is very dangerous.
Retraining is one-time event, it doesn't require equal cash flow, just that there is some cash set aside for it. I don't advocate permanent welfare, except maybe for those who are past retirement age.
It would have to work like insurance. Lots of companies with a chance of large scale disruption pitch in funds, applied in the rare cases where large scale disruption happens.
If you do end up making as much as the original industry it's because you are doing MORE than the original industry in which case you now have to question if the original industry didn't deserve to be destroyed.
Everything that can be software, will be software, what needs to happen is that the number of things that are software needs to outnumber the things that exist now. Software will create work for people to do as long as it keeps pushing what we can do as people. People need to adapt to a world with software at the heart, everything else is very dangerous.