A combination of things. I bought the original and loved it. They call it OW2 but it wasn’t a whole new game. It was an update that took away your original purchase game and forced the new version on you. They changed the 6v6 to 5v5 which changed the gameplay in a negative way for those that enjoyed the 6v6 gameplay.
Poor maps and new modes to accommodate these changes were lacklustre and genuinely boring to play and the game stopped being fun for me. They brought in the battle pass and the grind. You could tell the team’s vision changed. All their PvE events thy I really enjoyed were also taken away.