This does not happen in Java Edition but in Bedrock Edition, a Drowned jumps when it is walking on Soul Sand (not Soul Soil) and Mud. I can tell this is a bug because all mobs do not jump on Soul Sand and Mud when walking on it.
MCPE-165104
When a Drowned walks on Soul Sand and Mud, it Jumps
Resolved
Duplicate
0
Caleb Joung
(Unassigned)
Unconfirmed
Multiple
All Platform Versions
vanilla-parity
1.19.60.23 Preview
Retrieved
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We're tracking this issue in MCPE-162275, so this ticket is being resolved and linked as a duplicate.
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