Sure, sound engineers undoubtedly do a great job, but there are software programs and plug-ins that equalize sound automatically for the rest of us mortals. One example is Soundtheory's plug-in called Gullfoss which works on Macs. Another example is an app called FxSound which works on Windows.
I have FxSound installed in my PC even though I have never mastered how it works. It takes a person with a keen ear and great attention to detail, to learn how to equalize sound. It will definitely be easier and much simpler for some people as compared to others.