Computing History, as I understand it

 In the beginning, Computers were people who computed things.

Then mechanical adding machines came along and made them more productive, but demand kept up.  A phase change

Then tabulating and sorting machines, along with storage on cards brought formal methods of managing data to organizations. A phase change

Then electronic computers were put into place to start to do the computing.  The humans who previously computed were in demand elsewhere.  A phase change

There was 1 programmer... Alan Turing... then 100, then more... the rate of doubling about every 5 years, on average since then.

Computers were expensive, and it took time to learn to get the most out of them. Over time, libraries of code began to be commonly used, and operating systems were born.  A phase change

As the price of computers went down, and the amount of programmers and data went up, there were punch card operators, who transcribed handwriting to punched cards.

The computers still required maintenance, tubes to replace, circuits to adjust, etc... they were kept away from everything else in their own rooms. Operators were the priesthood that emerged to care for them.

Every new computer was faster, but incompatible... requiring frequent rewriting of applications to be compatible with the new systems. Most programs had a life of less than a decade.

Then IBM broke the rules, and the 360 could run 1401. Backward compatibility and legacy code were born, a phase change. Programmers didn't need to rewrite code, but by accident this created the Y2K problem.

Online teletype printers and time sharing allowed programmers and users to directly access the machines. Cardpunch operators were no longer needed.

Programming got a lot faster, and complexity went up.

Then Minicomputers came along, and were easier for end users, another phase change.

Then Microcomputers came along, and everyone had their own computer... you needed about 1 Administrator for 20-50 PCs, to fix the problems, and keep things going

Then things got more reliable, and went to the cloud, so administrators got outsourced, another phase change

It is now possible for a single person to deploy thousands of computers from a batch file.

The future is uncertain.... look back on the history, What makes any of you really think that there won't be another phase change?

As for why there aren't many old programmers...

Every 5 years the number of programmers doubled.... so most have less than 5 years experience.   There are about 120 times more programmers now than when I started, 7 programmer doublings ago.

We may, or may not, have a phase change that devalues programmers, developers, devops, architects, whatever you, dear reader, care to call yourself.

I myself did programming, then electronics technician work, then 15 years as a sysadmin, then 5 years making Bevel Gears....now I'm diving back into programming.

The future will have many changes... most of them productive. 8)