Wait wait wait. So having a game out for over 3 years with constant (but often unjustified) complaints from the community about over-levelled cards and it’s taken you this long to think about different level interactions on ladder?? Crazy
Of course we think about ladder levels but it's not the primary focus of our balance. The difference with Executioner is that it wasn't just 1 or 2 interactions here, he had more than usual and once all of those got flipped with an overlevel there were hardly any counters. We have made balance changes specifically focused on improving ladder interactions in the past, it's just not our highest priority since we assume players will eventually max out their deck, making level interactions less important than endgame balance between equal leveled cards.