I will agree many of them work "harder", especially in a gamified environment or a wage/contract environment.
The place I work at now has "performance metrics" based on closing issues and process automation. The "issues" can be virtually anything like a zoom call or a server health check ... create a ticket for it, close it and *boom* "performance".
The "process automation" mostly consists of shitty scripts that do one thing and only succeed if all the dominoes are perfectly aligned. There are literally thousands of these scripts but only maybe hundreds of unique scripts. It doesn't matter if anybody uses or even knows about the scripts all someone has to do is write a script, run it maybe once and *boom* "process automated". No QA, no design review, no release procedure, nada, zilch.
They are definitely working "harder" but the quality of work is lacking.
I realize this is not the case for 100% of them or all environments but in the places where they take over operations this seems to be the norm.
You bring up a good point. Quality of work. More importantly quality of outcome. Which kinda validates the IQ theory.