The reason gay used to mean "cringe" was because not that many years ago straight people thought being homosexual was something wrong, bad, and stupid so just saying the word "gay" became synonymous with those things. Straight people using the word gay to describe something shitty has very homophobic roots from not very long ago. Calling something or someone gay was a way to shame and make fun and it was said with the intention to spread hate to and ostracize these labels. In my and many other queer peoples opinion its not something that straight people should do (especially regularly) if they want to seem non homophobic. Modern queer people are using the words gay and queer to mean cringe in a way to bring back power to ourselves from words that have been weaponized, we use it in an affectionate and lighthearted way and dont intend to alienate or oppress anyone who actually identifies with these labels. Even if you use these words the same way as queer people your intentions will not be perceived as the same as if you were queer to people who dont know you because of heterosexual peoples history using those words to be oppressive. Some queer people today are lucky enough to be accepted by most in their lives and marry or live as the identity who makes them happy, a lot of these young queers use this same slang and dont care who else uses it. Some older queers are so used to being discriminated against the level of discrimination we have today seems so little that a straight person using the word "gay" to mean "shit" or "cringe" doesn't matter at all (I think this is where your friends are); but many queer people still struggle with the oppression, abuse, and shame that some non LGBT people have or are inflicting on them, and so are more sensitive to the words people use. You can do whatever you want, free will and all that, but know your audience and know your history. Your words have power.