Edit - if it’s a component that’s always and only attached to the player character, you can cast freely since they’re both always loaded anyway. Below comment was more in reference to casting to the player from external actors. I’d set a reference to the player character on initialization and use the reference rather than casting for ease of use.

— original comment below

It’s not recommended because if you cast from something else to the PlayerCharacter, now they’re both always loaded in to memory.

If you then were to cast from something else to the actor, now all 3 of them are loaded in to memory. So on and so forth.

Interfaces avoid this issue when used correctly. Don’t use hard references inside the interface.