Not everyone wants to see Easy or Ryanair take Manchester over for many reasons. I have no problem with them having a presence here but there are many people who dont want to fly with them. Not everyone wants to sit on a plane full of drunk Brits who clap when they land at an airport miles from where you want to be.
Now i realise thats not the case on every flight but they are some of the reasons people still want to fly with Legacy carriers.
Thats why you need the choice. Liverpool is a two horse airport thats about it and the North West as a whole will not benefit if you reduce airports to just a couple of airlines operating all the routes.
As for Liverpool losing pax i doubt that would happen as there are plenty to go around, however as Manchester was always the base they wanted then yes i can understand why Peel and some passengers may be wary of what may happen.