I worked as a project and later program manager at a multinational. I am unsure what a TPM is...
Hopefully it is just your perception that they provide no value, and if it is their own perception, hopefully they will gain sufficient experience to recognize their own value.
PMs, besides planning, measuring project progress and making sure the budget, tools and people are allocated, are also responsible for building the team, its values/culture, managing conflict, communicating the needs/issues/achievements of the project team to management and assuring the project goals align to business needs.
I know... blahblahblah... maybe an example works better?
The very first time I acted as a 'project manager' was in a team of 2 (me included). I was hired to replace a toxic employee and tasked to clean up the IT operations of a company's European field offices. As my technically brilliant colleague was getting me up to speed on the history, IT architecture, issues, etc., would often say: "I think we should do ABC," to which I often replied, "That's a great idea! Let's do it!"
Quite quickly, our collaboration took the form of me manning the phones, handling the communications with the regional leads, getting sign-off for the budgets and him implementing the solutions he himself proposed. I basically created the space for him to be successful.
Though initially I did miss doing the technical work, eventually I found it more satisfying enabling his, and therefore our mini-team's success.
Years after we had both left the company (our local field office was closed and neither of us opted to relocate) he told me how impressed he was that I had fixed all of their IT issues in under a year. I had to point out to him that all I did was listen to him, take his advice, and make it possible for him to implement his own proposals.
That is what a PM does.