Minecart ring sugarcane farm

Adil Gamez's own giant sugarcane farm, a hollow square tower roughly 31 blocks on a side with five floors of cane running around the perimeter and an open shaft down the middle. An observer on every row fires a piston the moment the cane grows, and instead of hoppers under the soil a fleet of ten hopper minecarts runs the rails beneath each floor to sweep the drops to two chests. It is a large, expensive, slow build: about 1,600 redstone dust equivalent, a thousand pistons, and roughly three hours of placing blocks.

jordanbanda5762 and MidNight35353 both replace the grass and the whole minecart rail system with mud and plain hoppers underneath. Simpler, same output, and it spends iron instead of redstone.
If the minecarts will not move, the farm is outside your render distance. GAMERWITHERminecraft says build it where you actually spend time, and this is the most common complaint on the video.
Jacqueline1Work plants and covers the first floor as soon as it is finished so it produces while you build the rest, and points out the same design runs bamboo if you leave the water out.
Rozarfie warns it spawns a lot of mobs inside the structure, so light the enclosed floors before you seal them.
Maltefjord0 puts a chest or barrel on top of every hopper. Hoppers check for items above them every other tick and with this many that is where the server lag comes from.
sifatakonda notes most servers with grief prevention plugins cap pistons and hoppers per chunk, so this cannot be built there at all.