Amount of damage an arrow can do is capped

Update: Just figured out the dmg of arrows is really capped. Attached is a video showing a setup that accelerates an arrow with 416 tnt to ~8km/s (400 blocks/tick) which with power V is enough to kill the warden 4 times over. However, only half the warden’s health as damage is dealt to the warden(the warden dies in 2 shots).(compressed vid finally attached)

Update2: The bug doesnt seem to exist (or exists to a lesser extent) on windows. When i tested the same mechanism on windows using power V the warden was indeed killed in 1 shot. (the vert railgun is now attached)

Note: I realised this may have to do with the damage of normal arrows being capped to 75 for some reason as they still deal 75 dmg even when i used contraptions using even more tnt to accelerate the arrow. (damage is not supposed to be capped)

Arrows from bows only deal half of the damage its supposed to deal with its speed.

(For arrows from dispensers, see MCPE-170186)

To see for yourself:

• Load the railgun provided using a structure block, but remove the dispenser and load the arrows on the carpet using a unenchanted bow because of MCPE-170186.

• Place a golem in front of the gun

• Fire the gun using the button

As shown in the video, the arrows only deal 75 damage(the golem is in final cracking stage).

However, as mentioned in the wiki, the arrow should deal 150 dmg(instantly killing the golem) as the measured speed is 75 blocks/tick (calculated in MCPE-170186) times the damage value of 2 dmg/(block/tick) for vanilla arrows on the wiki

Making the calculated dmg value 1 dmg/(block/tick). Is this the intentional true value on bedrock or is it unintentional?