You can certainly say that morale mattered before the training updates. There were high quality teams in League who didn't visit the game often and were underperforming (and no, I don't mean tankers). There were no direct advantages from preparation and training, the players' conditions were likely full and spectating didn't make a big impact, so what made their teams perform badly? Poor morale. Don't see a reason why'd they have removed the impact of morale after the updates either.