Magic, and magick is a homophone that is used quite frequently in the esoteric, and occult communities. These two terms come from the words magicus in Latin, and magikos in Greek, but those two words came from the persian word magi.
The word magic is generally used to refer to forms of stage illusions, marvels, mysterious tricks, and sleight of hand usually in the name of entertainment. It’s also usually used to refer to a feeling of childlike wonder, and fantasy.
On the other hand the word magick with a “k” refers to the ability to control supernatural energies, or is considered to be the act of placing your intent up on the world through spiritual, esoteric, and occult means. This form of the word magick was used in old writings, but this spelling primarily exist because manuscript copyists were paid by the letter resulting in repetitious random letter placement, mixed with a little bit of an old English correction. This form of the word was brought back into the public eye by Aleister Crowley back in the 1900s, and was used to differentiate it from its homophone sibling.
Does the spelling of the word magic(k) matter? I believe so due to the fact that the word magic(k) needs written contacts for documentation. Sure they started out their lives as the same word with the same meaning, and slowly drifted apart from each other, but these two new words are an adaptation of the old context, and are now used for clarification, and to make sure everyone is on the same page. Even just this little change of adding “K” on to the end of the word can lessen the confusion for people that are not as familiar with the practice as we are, and can lead to better comprehension of similar ideas, and practices. In this way it will also be set in historical context, and will make sure no manuscripts that are meant to be fiction, or illusion crossover, and become non reliable practices. This will also work vice-versa. You can see that this documentation is actually quite important by just searching the word magic, and then searching the word magick. These words have had a long history, and has meant so much to a bunch of different types of people who have worked with it, practiced it, and made it their livelihoods.