Chaos Orb breaks the rules by literally making contact with other cards, then taking them out of the battlefield in the process
The Creative team said they weren't staffed to create two planes in a single year (something we're equipped to handle now), so they suggested a story where something happened that was so impactful that it would allow for the complete shift in Zendikar's mechanics
Even when the combo is only two cards, neither one of them start in a zone where you can always find them and the opponent can interact by killing either the Enchantment or the Creature
Similar to the original Time Spiral set, Time Spiral Remastered will also include its own version of timeshifted cards, which will put more modern cards in the original Magic card frame
But sending it to a residential address is usually more expensive
As a result, it's often better to let an attack through rather than risk losing Prosper to a post-combat removal spell or combat trick