It's interesting though, the question really becomes, if 10 people used to shovel manually to feed their family. And now it takes 1 person and an excavater, what in good faith do you tell those other 9..."don't worry you can always be a hobby shovelist?"
They can apply their labor wherever it is valued. Perhaps they will become more productive excavator operators. By creating value in a specialized field their income would increase. Technology does not decrease the need for labor. Rather it increases the productivity of the laborer.
Human ingenuity always finds a need for value creation. Greater abundance creates new opportunities.
Take the inverse position. Should we go back to reading by candlelight to increase employment in candle making?
No, electric lighting allowed peopled to become productive during night hours. A market was created for electricity producers, which allowed additional products which consume electricity to be marketed. Technological increases in productivity cascade into all areas of life, increasing our living standards.
A more interesting, if not controversial line of inquiry might start with: If technology is constantly advancing human productivity, why do modern economies consistently experience price inflation?
You miss the important point, which is the productivity gain means the average living standard of society as a whole increases. A chunk of what is now regarded as 'toil' work disappears, and the time freed up is able to be deployed more productively in other areas.
Of course, this change is dislocating for the particular people whose toil disappeared. They need support to retrain to new occupations.
The alternative is to cling to a past where everyone - on average - is poorer, less healthy, and works in more dangerous jobs.
