I agree that this was probably the easiest puzzle this year but I do not agree that this was no more difficult than the average Times daily puzzle. For starters, at least nine answers are unlikely to appear in a Times daily puzzle, and some need a dictionary to confirm. A few others contain wordplay that involves obscurities such as archaisms that wouldn't be found in the Times.
When I solve the Times crossword I do it without recourse to aids of any kind, nor to a dictionary. I would expect anyone dismissing a Listener crossword as little harder than the average Times puzzle to be able to claim the same.
The editors probably felt there was a need to balance a string of fairly challenging puzzles with something rather easier. I found it enjoyable enough. The theme was appropriate, there were a few devious bits of wordplay (including one I cannot fathom) and the clue gimmick to provide the message was a departure from the norm.