We often hear that the best camera is the one you have with you. I disagree with the statement in part. Maybe it should be more like this:
The best camera is the one you are intentional and proficient with.
Of course you will only be able to take photos if the camera is "with you", I mean c'mon. By default that makes it the best camera. How else are you going to take pictures if you don't have a camera with you? I feel like this is something that only people who have not purchased dedicated camera systems would say. Or maybe someone who blew 10K on a paper weight because they don't take the time to learn how to use a thing.
The reason I stated the above is because I don't think it matters what camera you use, from a smartphone to a high end mirrorless, you have to know how to use it well. You are telling a story. You camera is just a means to an end. It's a tool.
Another part of the equation is your artistic ability and knowledge of the process of photography. People take this for granted in the auto-magic software age we are living in. The thing is, it still matters. A lot. A veteran photographer with a budget camera will almost always produce better images than a beginner photographer with a high-end system. Why?
They know how to use all the tools available to them in concert, proficiently. They adjust. They are intentional.
The best camera is the one the combines well with your skills and creativity-all of your tools-to bring your vision to life, or at the very least produce something that you are proud of.
So, get good with the tools you have. If you have to add to the toolbox, go ahead, but just know why you are doing it and what problem it helps you solve.
Never stop working on your craft.