Why are returning & older players are punished this hard - Lack of catch-up mechanics
Not only there is INSANE power creep regarding the champions there is also the fact that the quests/aq/aw meta require higher rank / higher star rating as time goes by. As a returning player I was very upset that my good 4* roster of ~1.5 year ago is just worthless now because of the ridiculous champions/nodes that they have to go against now and the fact that I missed out on a long time of meta progression which means that 5* and 6* champs simply outclass my roster.
In any other game, devs are eager to bring back older players; there are catch-up mechanics. In games, catch-up mechanics are supposed to be paths for progression for returning players that do not upset or undermine the current players efforts (so you wouldn't give returning players 5 5* crystals immediately but maybe only an increased rate of 5* shards until their first 5* crystal and that would be it).
In any multi-player game where the progression lies in numbers (health, attack power, ranks, stars, etc.) catch-up mechanics are essential. These mechanics are never behind pay-walls or time-gating and are available to all players but are skewed towards the benefit of returning players (since the current players might find the rewards not that satisfactory while returning players would love those rewards).
Don't get me wrong, I enjoyed this game when I first started in 2015 - and yes I gave a break because of real life reasons but now I am playing it again and having a lot of fun. However it feels like progression is unreasonably slow.