Passenger's riding position is too low for non-default-sized mobs

While passenger position was fixed in MC-259576 for default-sized Phantoms, Minecraft does not take mobs' size into account. The larger the mob, the lower the passenger.

/summon minecraft:phantom ~ ~ ~ {Size:80} 

/summon minecraft:slime ~ ~ ~ {Size:40}

Tested on Slimes and Phantoms.

The slime screenshot is for Size 40 Slimes.

The phantom screenshots are for Size 25 and Size 80 Phantoms.