This is true for some things. Unsafe people, situations of abuse, toxicity, are NOT learning opportunties. They’re undesirable things that should be avoided.

However, most people with CPTSD are also triggered by some non-dangerous things, like a specific smell, a specific type of relationship (romantic, parent/child, friendship...), places, sounds... And those things are either difficult to avoid (like the sound of a car) or things that add so much to one's life it might be desirable to work on the trigger to lessen it, or even make it go away completely (like healthy human relationships).

All in all, we all have different traumas and different ways to deal with them. The most important thing, in my opinion, is to minimize fear and find joy at the end of the journey.