Disagree entirely. This is already an iconic image.That may be the intention, but the piece does not convey it. I've run G3 twice and all I see is a random Fire Giant in a contrived position. The sense of space and movement is a mess. The central character appears to be trampolining upwards and is perhaps casting a spell but it's just a vague glow which conveys nothing. And that's the entire problem - this is a mediocre piece on any level (at least zoomed in like this) and it's a genuinely bad choice for the cover of the PHB. It will not be remembered fondly.
The DMG has a solid and appropriate choice, albeit it could stand to be sharper and more dynamic, and the MM has a good choice.