I guess you're not a pilot?
It is an axiomatic part of flying training that the identification of the point at which the base turn is commenced is readily understood by the student pilot. From that point onwards he/she is occupied with assessing power settings, attitudes and configuration changes to roll out on final at around 400 ft a.g.l 'in the slot' for the approach. They will then be in an aceeptable position from which to begin the landing process.
Whereas if the downwind point has bene extended, the task involved in setting up the final approach path is less easily qualified and unstable approaches are more likely; typically a student pilot will end up dragging it in on a shallow approach with a high power setting; this will lead to inaccuracy in the flare.
Furthermore, with any sort of wind (say 15-20 kts at circuit height), a 90 kt light a/c will only be doing 70-75 kts across the ground into wind, rather than 105-110 downwind, some 57% faster. So, to achieve a 'delay' for spacing, in a given time the a/c will need to travel much further downwind than it would into wind.
The effect of wind is far more marked on low speed ac; please believe that FIs teach circuit procedures from a background knowledge of quite some depth and experience. And get very annoyed at some ATCO who thinks he knows better!