What's the difference between Player and Platform within the Activity Dashboard Full View History?

Are they just same thing or is one a customizable name for the whichever platform is being used? Such as “My Living Room Roku” or some such?

As you may see you’ll have a ‘Device’ in ‘Player’ - then you’ll see it’s OS/Platform.

For instance mine will say:

Roku Ultra - then the OS is Roku
FireTV - Android
and so on.

Hmmm okay. So would you say something or someone has been hacked on this?

I would say someone changed the name of their ‘device’.

…by going to My Roku Dot Whatever and renaming the device… ‘that’, or anything else.

If you know someone in your audience with a Roku - they did that probably.
If you don’t - you should endeavour to aim a flame thrower their way.