In the UK it’s relatively common to have a safety pilot and I have been that safety pilot myself.
Almost always in my experience it’s for a PPL newly rated on a turbine helicopter such as a B206/R66 who has no turbine experience, and it’s normally for the first 5 hours after test.
The main reason is to protect the starts, as it can be pretty expensive if it’s overtemped, I don’t know if it’s an Insurance requirement, but usually a company requirement.
The dual controls will always be fitted, I can’t imagine that any professional pilot would willingly sit next to a low hours PPL without the duals fitted, (unless they were mental of course 😋
The PPL should not take it as assault on his her ego, but as a reasonable effort to prevent the engine being overtemped simply due to lack of experience of the PPL.
Hope this helps