I had the same problem drowneds didnt spawn so often so i decided to make a trident farm which it worked . But for the farm to work I had to stay afk 115 blocks above the base the farm was build upon (time depends on you for how long u are willing to stay afk). Also in JAVA converting zombies to drowneds will not make them spawn/convert with the trident in their hands.
Spyros
I had the same problem drowneds didnt spawn so often so i decided to make a trident farm which it worked . But for the farm to work I had to stay afk 115 blocks above the base the farm was build upon (time depends on you for how long u are willing to stay afk). Also in JAVA converting zombies to drowneds will not make them spawn/convert with the trident in their hands.