In version 1.13-1.15, it was possible to launch with riptide and quickly throw an ender pearl to travel substantial distances (200-300 blocks). This was because the ender pearl's initial velocity was based on the player's velocity at the time of the throw.

In 1.16, this does not work. If the player throws a pearl straight after launching, it does not travel quickly enough and the player simply collides with the pearl almost immediately after the throw, and goes basically nowhere.

To reproduce:
1. Create a small pool of water
2. Hold a Riptide III trident in the main hand, and an ender pearl in the off hand.
3. Launch out of the water with the trident, and immediately right-click again to throw a pearl.

I have tested this in both Creative and Survival mode, with consistent results.