The /ride command isn't allowing skeletons to ride spiders and zombified piglins to ride striders, however Illager ravager riders seem to work.

Steps to reproduce:

1. Spawn a skeleton or zombified piglin with a spawn egg
2. Do /ride @e[type=skeleton,c=1] summon_ride spider or /ride @e[type=zombie_pigman,c=1] summon_ride minecraft:strider

Expected result:

The skeleton should get a spider mount and the zombified piglin should get a strider mount.

Actual result:

It says the ride was summoned but couldn't be added to skeleton/zombified piglin.