That would be very, very unusual.
I mean, I tend to think more guidelines than rules... but even when not sitting thinking "this is a rule or guideline ", because I don't focus that way, I am aware that I do conform to many norms. Mostly. Sure there are songs and instrumentals where I have gone wandering from the reservation, but largely I conform to norms. For example time signatures. I might not plan to be in a 4/4 or 2/4 etc. but what I write just conforms to the rules about time signatures. For that matter I also conform to tempo, in that I work with a regular beat. I conform to musicals temprament, using instruments tuned to standard tunings that use a traditional western scale. I tend to stick the key I am in, and change key deliberately, so that is another rule that I follow. The melodies I use stick to a key, and without planning it to be that way even the chord progressions I use are for the most part appropriate to that key. Hell even in chord structure I obey the rules. I don't just play random notes together in the hope it makes a pleasing chord. How many rules is that I have obeyed so far?
Even if I use a sample loop created by someone else, or using a sequencer that obeys those rules, rules are obeyed. Then there are song sections. If I use a chorus, I just followed a whole set of rules, otherwise it is not a chorus. Same goes for a refrain. Or a bridge. In fact any sectional song. Hell, even if I do a through composed song I am applying rules. Perhaps not intentionally.
Then of course if I use words, they are actual words, not random vocal sounds. They are structured to mean something. That's a lot of rules, intentional or not, that I follow. Do I use rhyme? Stay within a genre or even use anything genre based.... then there is instrumentation. Do I have a bass drum? A bass line? Damn more rules I follow without intending to do so. I could go on.
My point is, even without consciously caring about rules/guides/conventions we follow them all the time, and yes they are important to us, even if we prefer not to acknowledge them. If we conform to a rule, deep down we care about it. If you use ANY of what I describe... you care about rules/guides/conventions. What you possibly don't care about is intentionally applying rules/guides/conventions.
I have yet to meet someone who doesn't follow rules/guides/conventions, or who doesn't in reality care, but I have heard a lot of people say they don't.
Of course, it is very possible to enjoy creatimg music while obeying rules/guides/conventions... because unless you are a very very rare creature... you absolutely demonstrate that is the case by saying your rule is to enjoy yourself!
I don't say all that to be picky, or argue a silly point. I say it for you. Because in realising that you probably already obey a bunch of rules/guides/conventions, and do actually care about applying at least those rules, it can free you up to consider other rules/guides/conventions, using rules/guides/conventions more intentionally, and applying them when suitable to benefit you, is a plus. Making the creation process more intentional and less happy accident is liberating, and more fun, if anything.
Not a problem for me either way, it is the way you think about what you do.
In music, rules/guides/conventions are there to inform choice. Once embedded they inform choice often whether we want them to or not. Learning how to use them to your benefit only increases the pleasure. Just like learning how to play an instrument, or how to sing better, understanding rules/guides/conventions just improves what we do, the standard of the end result, the songs.