There are lots of people that do not have the capacity to move up the 'value chain'. All they are capable of doing are 'simple' jobs:
> To enlist in the Army, aspiring recruits typically must take the Armed Services Vocational Aptitude Battery (ASVAB) test and earn a passing score. The ASVAB, with a maximum score of 99, requires a minimum score of 31 for Army enlistment.
> The ASVAB test encompasses various subject areas or subtests, including general science (GS), arithmetic reasoning (AR), word knowledge (WK), paragraph comprehension (PC), mathematics knowledge (MK), electronics information (EI), auto and shop information (AS), mechanical comprehension (MC), and assembling objects (AO).
* https://www.military.com/join-armed-forces/asvab/asvab-and-a...
If all/many of those jobs are automated away, how are those people supposed to make a living? It's possible to be 'too stupid' to even be in the military (or at least be in it and have a useful role).