Seriously.
How often have we seen contributors asking for advice on a new camera wanting "the best possible IQ" as a criterion. In such cases it is just a buzz word.
It's a bit like those pubs that advertise "good food served here". I've never seen one advertising "adequate food served here"
The irony is that for the type of output most people produce, the 'IQ' from anything with a 4/3 sensor upwards is virtually indistinguishable.
The 'look' of the image will have far more to do with the photographer.
If someone provides a proper use case and a budget, it's easier to advise. Large prints? Low light? Fast action? Some cameras will be better than others.