This is controversial and may not land for you, but I don’t believe in uncreative people.
In order to communicate the thoughts in this post, you had to use your creativity (and technique/knowledge of language) to decide how to use words to try to communicate that to other people.
That’s what music is too - communication - it’s just a different language/set of techniques. Which you learn, in part, via imitation (copying/memorizing songs), so doing that stuff is totally useful in moving towards the goal of creating more ‘original’ material.
The people whose bass lines and songs you’re learning aren’t working from scratch. They learned a ton of songs before they wrote any, and/or studied music theory to understand how music had previously been put together, so there are a lot of left-brained conceptual structures creating space for the more right-brained/intuitive creative element.
One more thought - in most human cultures these days, the left brain is given way more value and emphasis than the right brain, so it makes sense for some of us to end up feeling like we don’t even have a right brain creative/intuitive dimension.
But if you did bicep curls on only your left side for years, and then noticed your left bicep being a lot bigger than the right, you would know it’s just been exercised a lot less.
I think it’s a similar situation with learning music - if you want to exercise your right brain, you can explore right brained practice, i.e. improvising! You can do scale-based improv, like I approach a bit in the Beginner to Badass course, or you can totally turn your left brain off and just let your hands move on the instrument and see what happens.
Hope some of that is useful!