Scalable no portal gold farm

A gold and XP farm on the nether roof that runs in two modes. Zombified piglins spawn on magma platforms, a turtle egg walks them to a drop tower, and at the bottom you either stand there and kill them for the levels or walk away and let entity cramming do it. It gives about 400 gold an hour and 30 levels a minute when you kill by hand. The platform is whatever size you feel like building, which is why the magma and slab counts are missing from the list. Java only.

mobGriefing has to be true or the piglins ignore the eggs. Since 26.1 there is a separate mobGriefing gamerule per dimension, so setting it in the overworld is not enough, you have to set it in the nether.
The back rows of a wide platform never see the egg. A turtle egg only pulls from about 20 blocks, so keep the platform inside that or delete the far row on every layer.
The slabs are what stop magma cubes spawning on the magma. Use bottom slabs, top slabs are still spawnable and people miss that.
Since 26.1 leader piglins are taller, survive the drop and block up the top layer. Slabs across the roof kill them off.
Do not AFK on the kill platform. From there mobs spawn under the nether roof and eat the mob cap. Sit about 30 blocks away from the drop chamber, or on a separate platform slightly higher and further out.
In AFK mode the baby piglins survive the cramming because of their smaller hitbox. A dripstone spike on the floor kills everything the instant it lands. Do not stand too close either, babies with spears reach through the half block.