TTT's "if it ain't broke don't fix it" seems not to recognise that the suggested reason for the change is to save hard-up families money:
https://www.bbc.co.uk/news/uk-politics-61227622
(The words 'deck chairs' and Titanic spring into my mind upon reading that report).
However I still find myself agreeing with TTT that it's an unwise idea.
Equally though, I agree with Hymie that having non-safety-related items included in the MOT test can unnecessarily cost car owners a lot of money. For example, the steering lock didn't engage when the key was removed from my Saab's ignition. That didn't affect the safety of my car at all but it still cost me £650 to get fixed in order to get the car through its MOT!