I am hosting a 20 player server in 20w15a, and during our 5 day playthrough so far we have encountered numerous issues (especially regarding the new mob, Striders).

Here is a list of the encountered issues with the mob:

• Upon touching flowing lava, striders seem to start floating upwards and become unaffected by gravity.
• Right clicking with a Warped Fungus on a Stick while riding one does not boost the Strider.
• The Strider will accelerate at random times when being rode.
• No way to remove a saddle from a Strider (Not sure if it is intended, something like shift right-clicking on one to take the saddle would be great).
• When getting off a Strider, it is dangerously common that it will drop the player into nearby lava.

I have encountered some other issues not related to the Strider, such as:

• Enchanted glint does not display correctly on worn armor models
• When enchanted armor is worn, the handle of the shield shows the enchanted glint
• Ancient Debris not spawning in the new Basalt Delta biome (Not sure if intended)
• When Zombified Piglins attack Piglins (After being provoked), they might shift their attention to nearby players instead.

Overall the multiplayer performance in this snapshot is quite lacking, which is to be expected in a snapshot version of the game. Even with 128gb of ram dedicated to the server and a very strong Ethernet connection, upon reaching ~10 players the server slows down heavily.