Cannot perform a mace smash attack while mounted on a falling entity

Relates to MC-269202. The mace smash attack fails to activate while riding a falling entity.

Steps to reproduce

1. /summon iron_golem ~ ~ ~ {NoAI:1b,Tags:["bugtest"]}

2. Position a command block so it faces toward a chain command block
3. Insert the following command into the impulse command block:

   execute at @e[tag=bugtest,type=minecraft:iron_golem] run summon minecraft:boat ~ ~20 ~-2 {Tags:["bugtest"]}

4. Place the following command into the chain command block:

   ride @p mount @n[type=minecraft:boat,tag=bugtest]

5. Attach a button to the command block
6. Obtain a mace
7. Press the button
8. Strike the iron golem with the mace before the boat touches the ground

Observed outcome: The smash attack was not executed.
Expected outcome: The execution of a smash attack should occur.