So s1 was just a level increase iirc. I had zero noticed changes back then, but Im also a bit more aware these days.
S2 changes were harsh. I agree some warning would have been nice (I'm on server 1, so we get to be the beta testers lol)
S3, it was only a level increase. A 5% loss while using Emperor sets was noticed. The boss does hit a bit harder. There MIGHT have been a slight defensive increase but its really not noticeable. I lost half a % damage (literally 0.44%).
The real crux is the first come-first serve issue which we experienced in s1/s2 as the event/boss swaps over and people lose out in OW. This was addressed, except the 50% factor.
I think it was left at just a level increase to give some more fairness to players. Now, while I love a challenge and figuring stuff out - and straight up Squid Boss was my fun this season, I agree it would be nice to have more time to prep even for a nerd like me.
But, I really think with s3, the 50% isn't a factor really. Even the tryhards in my alliance, all they had to do was make some slight adjustments defensively/support/positioning and in most cases, damage went up ironically.