Summary
Drowneds are neutral toward iron golems, players and villageds outside water in daytime.
How to reproduce:
Spawn an iron golem/villager in the day
Spawn some drowneds
-> The drowned don't attack the iron golem/you/the villager until the iron golem/you attack them β
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is duplicated by
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Comments

In nighttime they attack. Also, MCPE-65098 hasn't been resolved as WAI, so no, we don't know if drowned are supposed to be passive in the day.

Updated title and confirmed. It has long been known that Drowned are neutral outside of water during the day, as described in the wiki. However, I cannot find an explicit statement that this is intended behavior in either the Java Edition 1.13 or the Bedrock Edition 1.5 changelogs, where Drowned were introduced.
The Bedrock 1.5 changelog does say
The Drowned - These dangerous, underwater zombies lurk in dark, deep water and will come up to the shore at night
I am not sure if this is a strong enough statement to declare Drowned being neutral on land during daytime to be intended behavior.
Thank you for your report!
However, this issue has been closed as Working as Intended.
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They don't attack, when are they 30 seconds out of water.
Did you try this at night time? Because drowned are usually passive during the day. If you did, itβs probably a bug.