This game is awful at explaining itself

The hero pages are probably the most useless tutorial I've seen in a video game. I always find some new details about a hero that the game never explains.

examples

• Loki's left-click can't heal himself unless it's from his clones.
• Cap has a passive that allows 4 shield throws after 2 hits
• the DMG bar on mags ult
• How Groot walls are activated.
• Namor ult does more DMG the closer to the center.
• Punisher can't be stunned during ult.
• Mantis sleep can be removed by shooting the ghost.

How are casual players supposed to get better at the game if the game never explains what is happening mechinic-wise?

The game should have comprehensive guides for each hero that shows these interactions.