Alchemy as an excuse to worsen the economy
Digital only cards are absolutely fine in and of themselves !
However, up until now when bans occured you acknowledged mistakes had been made and gave us wildcards back.
With Historic and Historic Brawl becoming "live" formats you will have the opportunity to directly put your hands in players' collections and modify cards already acquired without any compensation.
The fact that both versions are still technically there doesn't mean much if only one of them is playable in Historic and Historic Brawl.
Magic Arena may be digital but it is still a Collectible Card Game !