I think often PT places are expected to "fix" the problem , or at least show a good rate of improvement, in 6-8 sessions or 2 sets of sessions.
For TOS or chronic RSIs, that is just not enough time. In that senario they do tend to press forward too quickly, causing problems for us.

Often those injuries took many years to build up to the extreme/chronic symptoms, those symptoms cannot be reversed in a month or 2.

I do think often some sort of skilled manual or "hands on" therapy is needed. Self stretching alone often doesn't do all that we need. But each case of TOS is different.