What's the quality that gives some lenses (like Minolta G) a "3D" look?

3D to me just means a correct or natural perspective/view.

If it's 3d, a cube looks just like a tall-square which is a cube:)

If the cube suddenly looks like a tall-parallelogram or tall-rhombus then there is front-to-back compression (depth/distance distortion) and now it doesn't look quite 3D or true anymore.

A corner view of a rectangularish building or object with an appropriate front-to-back distance.... that's 3D.

That same rectangularish building now with less front-to-back distance in the picture... not 3D.

A landscape shot that does not have the great/appropriate front-to-back depth... not 3D.

From an angle, a model's face/head that looks like a normal head when we look at this person (not squished front-to-back thru the lens)... that's 3D.

A round ball that looks like a round ball... correct perspective/view... that's 3D.

A bird that looks rounded/well-fed or just like a normal bird... that's 3D.

A spherical moon (or hot model) that looks like a spherical moon (or has defined features).... that's 3D.

A spherical moon that looks flat in the picture... definitely not 3D.

Normally a prime/telephoto lens will be good and pictures will look 3D.  This is why some people use it (others buy it because it has a large aperture).  Zoom lenses are more tricky/difficult and the 3D-ness may vary throughout the mm-range and some lenses do it better sometimes.