I guess that's one "problem" with the Moon Lord fight fixed.
However, I personally feel like - now that the developers are going hard out of their way to fix the common "cheese strats" - is that there is a much bigger problem with the Moon Lord fight, that being the fact that especially on your first time trying to beat him, for every 15 minutes you spend on attempts, you have to spend just as much if not more time grinding pillars for more Celestial Sigils, which is extremely boring and outright kills the pace of the game. On top of that every Celestial Sigil still has that 60s delay to it, which might not seem like much at first but it really does add up if the boss in question is difficult enough to take you dozens and maybe even hundreds of attempts. This is exactly the kind of thing that makes players quit: not just a difficulty spike, but one that forces waiting and hollow grinding upon the player as a punishment for dying, effectively discouraging them from playing the fight at all and making them feel unengaged.
I won't comment on the Rod of Discord grind, since I trust the developers to be sensible enough to either make the deathray reasonable to dodge without it or the other kind of "speed cheese arenas" (minecart, fishron+water bubbles, asphalt, teleporters), or, if it is basically made mandatory, shorten the grind on it. Personally, it's a cool item so I would like to see it become more accessible especially at this late of a stage in the game; maybe even make the Nebula Pillar drop it or something like that.
On the topic of pillars, I sincerely hope that event is reworked too. Having to stand on the very edge of the pillar area and spawning monsters one by one (otherwise you get completely destroyed) isn't very fun. Maybe have a requirement for the player to actually stay in the middle of the pillar area all the way through, but nerf the monsters and/or spawn rates slightly so it's reasonable.
Basically everything else is perfect.