So. Using your phone to take a picture is cheating too. You did not study years to perfect your painting skills, you used no canvas, did not mix your paints, yet you press a button and get an image anyway. You did not even need to select the light and shutter configuration or the focus for the picture. A cheat it is.
And yes, such images should not be entered in an oil painting jam. There are ai game jams for such things. And without surprise, most jams restrict ai usage in some way or compeletely. Especially, if it were a jam about learning to code.
If you created your own version of pacman from the ground up after watching how the arcade version works, you created plagiarized it.
Also, you very likely do not create it from the ground up. You will use libraries that other people programmed. You most likely will not write assembler, or even a low level language. In these times you will use a game engine. Probably Godot or Unity and create a game that is a modification of one of the tutorial games that has enough features that you can modify to look like a pacman type game.
And curiously no one takes issue with the fact that you just copied a known game idea. Without consent.
Hobby usage of ai is not the problem. It is an enabler. Just like using Godot and other engines are. Or even that scratch game site for kids. It enables people with little coding knowlege to create a game. And "little to no coding required" is one of the selling points of many game engines aimed at that market of hobby developers.
The problem is professional ai usage. AI assets. Games with a big budget, that chose to throw it away for ai tokens or said assets. Studios that could hire artists, but chose not to. And outisde of video games, all the ai hype and spam. Crap like an ai reading an ai script as a youtube video. That's even worse than those fake life hack videos from content farms. And problematic are the people that use ai to spam even more slop games, as they previously would have spammed with those no coding required engines.