People will only 'go obsolete' with their jobs if they refuse to continue their education. Not much call for punch card readers these days even if it was a big calling at one time. Those people, if they didn't pick up new skills, are out of the job and 'obsolete'.
A human being should never be considered obsolete and disposable on the basis of their skillset. Period.
And besides, your expectations are unrealistic for many reasons.
1. A person who gets laid off because they're not needed anymore still needs to have some way of supporting themselves while they retrain for something else. What you're saying is that someone who finds themselves without income should somehow magically afford to continue living and paying for a new education, until they have an income again.
2. Many of the people whose jobs are going obsolete have been doing those jobs for a very long time and are getting old. Besides the fact that it's generally more difficult for people past middle age to learn new things, especially pertaining to technology. It's really unfair to expect someone who had another 10 years to finish up preparing for their retirement so they can live out the last years of their life expectancy to suddenly have to set themselves back who knows how long on a bunch of educational debt that will probably keep them working until they die.
3. There is simply less work that needs to be done. We're going to hit a point where actual labor is in very, very low demand, and all that's left is scientific, creative, medical, or engineering work. Plus, the standards and complexity of those types of work is constantly increasing. Not everyone is cut out for it. You can't expect every person alive to go out and get a hard science or art degree to survive.