This bug started from the most recent betas of 1.17 (around 1.17.0.52),

The only gold farms that worked in previous versions of Minecraft Bedrock, stopped working completely. These used portals turning on and off to generate zombified piglins. These farms were not taking advantage of a bug:

The farms took advantage of a mechanic that existed, which was that a lit portal had a probability of 1 in a certain number of ticks in the game to generate a pigman zombie south of the portal.

• This probability increased the higher the difficulty level of the world played.

• In Bedrock's version, this probability increased considerably when the portal was turned on

The problem is that in this version, no zombie piglin appears, neither because of the time, nor because of turning the portal off and on, nor because of the difficulty of the game. This clearly broke all existing gold farms in Minecraft Bedrock, as well as this mechanic 

 I'm not sure if this has anything to do with it, but I have noticed that on these farms when turning the portal off and on, it doesn't look like it should. The portal is turned on extremely slowly and in parts, the animation is seen as divided into cubes and on occasions it does not even turn on well.