>>47116126New mechanics will provide an entirely different experience. Even if everything they include boils down to Fairy typing, hidden abilities, Gen 5+ QoL improvements and new moves, it's already massively different. If they go all the way and include megas, new regionals, Gen 5+ Pokemon, then it would be almost an entirely new experience.
Don't get me wrong the games look like underwhelming shit and Gen 4 should have got at least an ORAS tier remake but the point of playing a remake for me is playing with new mechanics and improvements so as long as they're in I'll buy it (used)