IMO this attitude is problematic. It encourages people (especially newbies) to think they can't trust anything, that software is by nature unreliable. I was one of those people once.
IMO: Exactly the reverse. That's how we get clients clicking and agreeing to everything presented without for once thinking critically.
In 6 working years (MSP) I had probably less than 10 occurrences of clients questioning a security concept from their own action.
If we didnt protect them from their own stupidity, the amount of cyber breaches would explode...
Just recently:
A client: I clicked on the box that is asking me for domain credentials.
The client didnt say what type of window it was or what happened before/after.
The client juat contacted us, because the pc wouldnt connect to the network and thus was unusable... >_>