A crutch is a figure of speech that describes something that is used as a surrogate or substitute for a more ideal solution or approach, as in the use of medical crutches as an assistance device for walking. The term also implies a degree of habitual laziness.
"A debugger is a crutch for programmers too lazy to add proper logging to their applications."
"Using pre-made pancake mix instead of making it from scratch is a crutch."
From a gaming perspective, a crutch is the use of an item or technique that is considered easier or generally way better than most options available. As if using a "three-wheeled bike" compared to a "two-wheeled bike"
"That weapon is considered a crutch because it's so easy to use and it kills peoplefast"