You most certainly can make usable stuff with 3d printers. The low end consumer grade units require a lot more skill and experience to do a good job, but compared to 10 years ago, it is a much nicer world. Just know that even with higher end gear, you need to understand the materials and process to design and fabricate parts that will do what you want. A trinket to sit on a shelf is easy. A structural component or a toy, less so. A structural component like the camera mount takes a good bit of consideration. A better machine reduces the number of issues, but does not eliminate the need for care in design and process.
(note that I am not a heavy duty user of fused dep machines, and rely on the expertise of others for critical parts done this way, which is not often in my world)