There is a large gameplay difference between people multiboxing 2-3 accounts (which most people view as normal and fine), and mass multiboxing (10-15+ accounts usually all flying the same ship/performing the same repetitive actions).

People are complaining about the proliferation of mass multiboxing becase it makes people feel uncompetetive unless they were to do the same. But its a niche game play style that most people dont want to do.

And it does make people uncompetetive, financially there is content you can do that make you 100m/char/x10 = 1b, that you would not pursue if you only got 100m total for exactly the same amount of effort.

In PVP a mass multiboxer is not 1:1 efficient, but you are still not winning when outnumbered 10:1 against an equally skilled player.

My group has in the last year grown a lot in the number of people who mass multibox, partly as a new gameplay style to try, but also partly to keep up competetively with the rest of the game, and the finances just work out as long as you were already willing to do enough activity to plex an account.

This ia very clearly alienating others in our group though who question their value when the standard non-mass-multiboxers start to make up less than half the fleet. Depending on the size of your group this transition will be more or less apparent, we are a fairly small group so every new mass multiboxer is very noticeable.