Tailorism was good for simple, repetitive and immutable tasks, where the only planned improvement would be the worker. If the task was to be revised, it would be top down from an 'analyst' that designs a new task and test it on workers.
What changed this perception ? Toyota like factories, and the idea that tasks should progressively evolve, workers can change their environment in non top-down ways. The metrics was not how much time it took to do a single task, but how much the whole pipeline was efficient.
It's just an example, but I think time tracking should be a relic of the past, as an idea that was too simplistic and too seductive to micro-managers to be really valuable.
It's easy for one person to increase in time-tracked productivity in ways that decrease the aggregate productivity of the group they are in.
Sometimes, the person is happy with their own work and unhappy with everyone else's, and they have a blind spot because it's so hard to understand how improving their own productivity can slow down other people so much to be net negative.
But I've seen it, I think it's real. I think it's sometimes a very strong effect, which can make or break a business.
Just like manufacturing pipelines, people affect each other's work in non-linear ways that clog up the system.
As with pipelines, performance improvement lies in working with those non-linear dynamics well enough to reconfigure the system, so each person can excel at their best.