I am most impressed by the fact that the entire shrine of resurrection is just gone.

Gloom is 100% not weaker than malice. Gloom decayed every weapon in hyrule and direct contact with it deteriorates your life force. Malice did normal damage while gloom seems to attack people on a spiritual level. It even destroyed the master sword.

I think finding broken down shrines deep underground and being able to find undecayed ancient weapons would be absolutely awesome

It’s kind of sad they removed everything, like I get slot of the things they removed, but leaving behind maybe the towers and a few dead guardian would give a much more satisfying canonical answer, especially if someone ACTUALLY ACKNOWLEDGED IT, just some dialogue like, “a lot of sheika tech went dormant so pretty much everything was torn down for parts since it was on longer uses full and could pose a threat” would be SO much more satisfying than people acting the the ancient sheiks tech, a core element of the last game both lore wise and I’m terms of mechanics, never existed is so sad. like I said, I wish they didn’t remove every possible ruin and had focused some of the efforts of Romeo in every trace of both on explaining it.

Where did Kass go and why has everyone completely forgotten the divine beasts

My question is how the Astral Observatory below Hyrule Castle is gone too, despite nobody visiting. In BOTW, a passageway in the Library leads to a room that is implied to be right next to the Observatory, having a Sheikah wall. Upon revisiting in Tears of the Kingdom, the Sheikah wall is replaced with stone.

You can actually get the divine beast masks without the amiibo. After completing one of the four regional phenomena dungeons, talk to the person you just beat the dungeon with (Tulin, Yunobo, Sidon, or Riju) and they will give you a side quest, the reward for it being the appropriate divine beast helm.

There are holes to the underground where a lot of the shiekah shrines were, so it's possible that some weren't completely dismantled, and instead ripped apart by the gloom creating the holes to the depths. No idea if it's where all shiekah shrines were, or just some of them, but definitely at least some.

My current headcanon is that purah probably had them scrapped for parts to use in her own experiments.

The only guardian I've found this the one on top of the ancient tech lab in Hateno, and I'm pretty sure the only reason it wasn't moved was because its a part of the building asset so it would be a pain to remove.

One of the most notable things about TotK, is how the map feels entirely new and fresh despite being the same one from the previous game.

The Sage helms are definitely available hidden away in game. I found the Rito helm deep in a cave in the Hebra mountains. I had to complete a puzzle overseen by a Zonai statue. It was really cool to stumble upon!

the thing i have a problem with is the fact that none of it is mentioned at all. no mention of the beasts or guardians, spare for one on the hateneo tech lab, but other than that it isn't mentioned