I have to agree with most of the article, apart from this bit "
Passengers vote with their feet. While Luton has a commanding position with the M1 running close by to the west and the A1 not far away in the easterly direction, it is expected to move something fewer than 16m passengers this year"
Passengers vote with their bank balance. Those travelling low-cost (nearly everyone) will put up with poor - or worse - facilities if they are only paying peanuts for their flight. So long as passenger numbers continue to rise (already more than the quoted "fewer than 16m this year"), airport management will happily ignore the adverse publicity which, as the article says, has put it at the bottom of the UK airport league table for decades. As someone who has worked at the airport for many years, I despair at the (mostly justified) complaints I come across, but I guess my comments above are vindicated by the graphs below.
Here we have the LTN and STN passenger numbers for the last 20 years:-
LTN
STN
Stating the obvious but STN is only a couple of million better than its peak in 2007, while LTN is nearly 6 million above its peak in 2008 (data from Wikipedia).