"A camera will not make you a pro at anything, its an aid, not a life saver."
Yet that is what some insist, which is why when I read such statements I think "this guy is not a pro". My experience has been that the more a person talks about what pros want or need, the less likely they are to be a pro, or to understand what goes into a given pro choosing a given camera system.
Professionals knows what tools they need, and they will use the tools they need so they can do the work.
You are welcome to go and look to any professional tools arsenal and see that I am totally correct.
The only difference is that many fails to understand, is that there are all kind professionals who do same area of work but different kinds and different ways with different results.
It is like a different driver has different setting values for their F-1 race car even when the car is exactly identical by every possible physical way to other driver car. But the software and adjustments makes huge difference to the driver capabilities to pull things differently, and that difference is so big that it is like driving a different car all together.
The same thing is with photography, there can't be a one universal perfect camera that does everything perfectly for everyone. You can either pick 3 features from 10 and get those 3 features 99% of best possible way, but 7 of 10 are below average or impossible. Or you can try to get all 10 features from 10, and get only 30-40% functionality from everyone, generating jack of all trades, master of none camera.
If you want cheap and good, you need to buy two.
If you want camera for photographers, it is compromise for videographers. If you want camera for videographers, it is compromise for photographers. If you want to please both, you are compromising both. And some compromises are such that simply are too much.
And professionals knows what they need and they simply get it. If they need camera for sports photography, they get camera designed for that. If they need camera for video, they get video camera. If they need silent camera, they are not going to get a camera with huge mirror clacking no matter how good other features are in the camera.
And when a professional say to you that they can't use a specific tool for their work, it does not mean that everyone is limited by same manner. But that doesn't either mean that professional is the only one in the whole universe who has the limitation from it.
You are as well welcomed to go to different hardware stores to look how there are dozens of different kinds tools for so simple tasks as pulling a nail or screwing a screw in. Or simply go to camera store and look how there are dozens of different kinds tools for different kind people, and none of those are perfect for everything.