What really sells Chop Goblins is how much game-y it is. Pretty weird thing to say about something that doesn't try to experiment or present some unique with its gameplay at all. The only thing that could be said is that Chop Goblins features lack of jump button just like in first comers of the FPS-genre like original Wolfenstein and first Doom. In that sense, it's definitely retro besides the graphics.
This limitation for the player resulted in more grounded look towards the design of Chop Goblins. While the arenas themselves can't present a challenge for similar game with the ability to jump, here (it seems) player will have to think twice before moving forward. Carelesness is something that most modern shooters try to aboid by giving more options to escape, but this game goes the other direction and asks to just consider your movement.
Strictly speaking, shooters are always about navigation more than anything else. Even the act of shooting a target can't be done without putting your cursor on it. While movement shooters present an additional challenge with more options to navigate, it can be argued that they're temporarily break the 'shooter' gameplay for one moment and become only about 'movement'. Getting rid of options to move helps focus on combat more closely.
Obviously I'm not saying that movement shooters are bad in any way, I just wanted to point that out.

I care for this little silly game too much to admit. It's short and won't waste any of your time.