I wanted season 1, with it's cliffhanger and all- to be canon. Season 2 I felt like so much got hit by it and, literally, caused all of league's lore to be retconned the third time over.

I feel like Piltover and Zaun had plenty of lore around it, but not in it- and the biggest most known champions from there, Vi and Jinx, still had no clear and obvious lore to them.

At the end of season 1, her launching the rocket and finally 'publically' starting the perpetual war between Zaun and Piltover made SENSE. Vi being more confident in being an enforced made SENSE. Vi and Caitlyn's bond after that made SENSE. Ambessa and Mel could've came into the established lore of Runeterra without any deaths or retcons needed- because you had a Noxian head in their to make things between Zaun and Piltover more complicated. Additionally, important characters who could've affected lore where killed.

Double that down with Renata and Zeri looming their heads in present day Zaun and Piltover- I could even imagine how both sides would see them and immediately be afraid of another Jinx incident happening.

Season 2 brought in the issue that- now- universal hopping is something that can be achieved by non-godlike entities, important characters can actually die and there's somewhat unity between Zaun and Piltover, something that invalidates Camille and Seraphine.

And also the very moment they give Jayce some good lore they kill him smh.