Looking for Goldilocks

Weeks ago, an announcement about the discovery on an exoplanet where it appeared possible for an atmosphere with precipitation to exist led it to be described as an “earthlike planet,” and suggestions were made about its potential habitability.
Very little was said about its structure being far more like Jupiter mostly gas with a tiny rocky core very far below the cloud tops. That’s an important component of the composition in a description mentioning ‘habitability’ and ‘earthlike’.

Mass determines if the object produces a gravity field capable of holding an atmosphere for some length of time. Venus and Earth are massive enough, Mars was only able to hold a thick atmosphere for a comparatively short period early in its history.
Position relative to their host star: the ‘Goldilocks (habitable) Zone’ ideally looking for a distance where water can exist as a liquid.
Density of exoplanet candidate ‘Hot Jupiters’ have been