The latest release of Alchemy was the final straw for me, an avid MTG player since Scars of Mirrodin, and spender of on average around £100 a month on Arena.
The shear volume of rares being released, the lack of any in game mechanism for 'dusting', trading, or likewise, and understanding that cards can now be reduced in quality with zero refund opportunity having removed all consumer confidence in my purchases has just made me delete my payment details from the Arena client, and I'll no longer be a pay to play player.
I fully understand that Wizards couldn't care less about my measly £100 a month, but having loved this game for nigh on a decade, I felt I needed to voice my exasperation at this final move by Wizards to force me to stop wasting my money on your company. I guess I'll save it instead or something sensible.