It is possible to identify a trauma from events a client reports from their life. It is also possible to hypothesise the impact of said trauma on one's life. However, the key word here is that it is stated as a 'hypothesis' not a 'fact'.

But a therapist pushing the idea of trauma on a client? Red flag.

Similarly, any therapist (or human being) who claims that it is just *one* thing that is the cause for *everything* - that sounds more like propaganda than good therapy.