The job-saving technology will live forever, long after the people who are temporarily displaced die. You're doing an immense amount of good for the untold number of people who aren't even born yet.
Technology is also global, but the political problems associated with eliminating jobs are problems on a state-by-state basis. Is it immoral to develop a technology just because some political systems are incapable of handling the gains in productivity, while other states are?
If that notion is correct, moving towards an educational model focused around creating the components needed for general entertainment (video/AR/VR/Music etc) might alleviate the problems we'll face.
Where are these people getting the money to spend on entertainment if they aren't working? I don't think this will happen.
What I do see happening, however, is that people have less free time between juggling more than 1 job and a side gig with Uber/their ilk.
I grew up in a country (Finland) where people bag their own groceries. The table behind the cashier just has a bit more room and some dividers, so even 3 customers have room to bag their own groceries simultaneously.
So an utopia without the "grocery-bagging class" is certainly possible.
So what is new? We have been automating jobs out of existence for a long time. Every era has had a lot of people that are redundant, every era has had useless governments get to grips with it.
Recently I automated three jobs out of existence, making the computer do the data entry work with the customer filling in forms. This is great for the customer as they now get what they want done instantly instead of having to wait a week for the human to do what the computer can do. It is great for the company as 3 people don't have to be managed, provided office space and paid. But as for my colleagues?
I obviously have had thoughts about automating my friends on the next desk out of existence, how I see it is that there are actually plenty of vacancies in the company, there are plenty of vacancies outside the company and the writing has been on the wall for the last year regarding the changes we put through. 2 of my 3 former colleagues are now working elsewhere, having moved on fine, but there is the one that did not step up and go for other interviews within the company or look elsewhere. Now I am sure that government handouts are available, however, if someone does not look out for their own job and assumes it will always be there for them, what can you do? Is it always the government's fault in this situation?
My above sentiment is a tad Thatcherite, it was Norman Tebbit who said 'on your bike', i.e. if there isn't a job for you in your home town then you have got to move, the government isn't going to magically create a job for you. The 'on your bike' remark didn't go down too well in the 1980's, but 'on your bike' it has been since then.
There comes a point where flexibility and gumption don't get you far enough. When the pool of good quality jobs shrinks so much that the ecosystem cannot support the species.
I'm not calling for a halt to progress. If you hadn't automated away those jobs someone else would have. There are very strong economic incentives to do so. I just wish governments would see the writing on the wall and start planning for the future where the status quo leaves most people out in the cold.