Digital format megapixels are a marketing driven item.
A collegue of mine actually designed most of the lens systems for 2 of the biggest names in DSLR cameras, he’s been a camera lens system designer for more than 50 years (yes, he’s in his 80s and still sought after by the camera makers). According to him, unless you plan on spending more than $10K, you might just as well buy a 3-1/2 to 6 Megapixel camera body, because the lens system won’t give you a better image than that anyway, no matter how high you go in megapixels.
And for the film purests, 29.5 megapixels is equivalent in a 35mm format to the very best smallest grain film ever sold, provided your lenses will use it.
My DSLR, a Nikon D40, is only 6 MP. Nikkor lenses are SUPER sharp, and I never had a problem with clarity or detail...
“the lens system won’t give you a better image than that anyway, no matter how high you go in megapixels.”
Some imagers are getting so good that there’s talk of (if not already) mapping out the lens’ flaws so the image processor can correct for imperfections.