An improvement to UK carry on rules from January 7

Last month I posted that UK carry on rules are to be relaxed ... maybe ... for some. The Department for Trade has released info on which airports will allow 2 carry ons from January 7th (see The Guardian for example).

The news is better than expected, although far from perfect. Most, but not all major UK airports will allow 2 carry on bags. Notable among the exceptions are Edinburgh, Glasgow and London Gatwick. Many secondary airports are still restricted to 1 carry on.

More airports are expected to be added to the "allowed to have 2 carry ons" list over time.

Which begs the question - why can't they just make the rule 2 carry ons are allowed? Simpler and less confusion.