"Mint" has a meaning. It is very well understood that "mint" refers to as new condition, an item as if it had just been minted. For a camera this would mean no signs of use, with the box, instructions and any accessories originally packaged with it still present. Perhaps it *has* never been used, but certainly no signs of use.
"Minty" is a BS term invented by ebay sellers to describe something which isn't in as new condition, but the seller wants to make it seem more special than it is. There is an accepted term "near mint" which would be understood to mean that the item's been used enough that it is distinguishable from a brand new item...but there is no damage.
That G1 with the gouge, is not "mint" under any reasonable understanding of the word. "Excellent condition apart from one scratch - see photos" would be appropriate.
There's not really any wriggle room. The word has a clear meaning and etymology to back up that meaning. Words do often change and evolve but in this case there's no wriggle room. "Mint" is really a binary term, there are no degrees of mint-ness. It is, or isn't.