I mostly found TLM a disservice to people who reported to TLMs. They didn't have to earn a promotion as both an engineer and a manager at the same time, so many optimized for their own engineering promotion and any managing they did was out of the goodness of their hearts.
As a devil's advocate (I don't work in Google or in a similar role) but if the requirements for engineering promotion are similar for technical managers and engineers, while the first have to manage people then this is just how the system is set up. In this case I think blaming the system more than people is justified, and Google decided to dismantle the role for some reason.
