They can't just continue to print tons of extra cards all the time while there allready is a massive oversupply. It will devalue cards more and fewer players will be willing to buy them anymore. The system will also be flooded with a ton extra DEC that is now sitting locked in the dao.
It just isn't a strategy that works long term always using the same trick of 'we need something, ok lets print a bunch of extra cards".
I guess we'll see what it does for the price of SPS even though I'm quite sure it will end up as a temporary pump & dump.
I feel that but 2 sets per year is not a lot of extra cards and is in line with what most other companies do - like MTG