Enderman spawn rate is too low on bedrock

I tried to build this simple enderman farm as shown in video
https://www.youtube.com/watch?v=ckhe8ws-a4w

I attach a screenshot of it working on my realm server

 

And here is the same trap I build on java edition (1.14.2) working as intended

 

I would like to understand why the spawn rate is so low on bedrock, is this intended?, is this a bug?, for now, playing on bedrock edition is very boring with this problem with farms in general

 

please have a good day