Fret placement is mathematically determined by scale length. The range from the lowest to highest note is constrained by the scale. There is a question of how many frets a luthier choses to provide, but the maximum number is limited by the scale length, though certainly usefulness comes into question as frets can get so narrow as to be useless. That's why you see some sopranos with only 12 frets and others with more.
We have always only 12 frets in the first 1/2 of the scale (see the figure below). We can not add many frets in the 2nd half. The only way to expand second half is adding scale length. We often shift neck joint from 12 to 14 fret.
I get what you are saying: extra frets may not be useful on a soprano because the spacing will be tight. Whether they exist is influenced by the scale length of the instrument and whether they are usable depends on your dexterity. But those extra frets do determine the effective range of the instrument.
To answer OP wherahiko's original question then, it might be best to suggest that soprano ukuleles and larger scale instruments might better suit different styles of play. If you want to use 100% of your fretboard real estate, a soprano may well be more difficult to play depending on your personal physiology and skill. If you are just strumming on the first 5 frets, then it all comes down to preference.