Foil reprints happen in special sets (Conspiracy, Battlebond) or curated small sets (From the Vault, Signature Spellbook) and the occasional judge promo/RPTQ release
The buyer gives up a card they don't need for a card they do, which is a regular trade beyond the price tag, but the buyer doesn't lose stock
They dont let you play the original card, but rather create a copy of a creature
Even if you dont deal a ton of damage this way, triggering saboteur abilities twice is already strong
No tap on the mana-making ability was a silly choice, and building in its own wincon by giving it the Final Fantasy wizard-pinging ability caps it all off
Finally, given that some new artifact-centric cards have been printed in Modern Horizons, I expect players will be trying to find the spiritual successor to Ironworks, meaning the Ouphe will be great there as well