The datapack attached here is admittedly still quite buggy, I've fixed a problem with the rain, but the drowned still sometimes gets stuck in blocks underwater (I think???) and so it starts throwing them normally because it doesn't think it's in water.

Also make sure the drowned's actually holding a riptide trident, it doesn't work with normal ones.

I'll fix the bugs at some point maybe idk, someone yell at me to do that if it's a big problem.