They don't lack them, but it's indeed not a scaled design (if it were a scaled design, then the 14mm would be larger than the smaller focal length ones). Actually, it looks like the line from 14mm onwards to higher focal lengths is close to a scaled design, while the shorter ones look like a design that is not scaled (i.e. with a Smyth lens spaced progressively further away to decrease the combination's effective focal length.)
the reason for that is simple: the 14mm has more or less comfortable eye relief. If you were to simply scale the design down then the eyepieces would become less and less comfortable in shorter focal lengths since the eye relief would also scale down with focal length. If you slightly scale the design down and then increase the distance between the negative and positive groups, then you can get a shorter effective focal length eyepiece with the same eye relief (the price you pay for not scaling the design down is that you need bigger and wider lenses than if you had scaled it; the eyepiece is also longer but there is something as "short enough").
If you want to see a pure scaled design, here's the type 5 Nagler:
These do indeed get bigger and wider with increasing focal length.
You could make a 8mm T5 that was twice as short and twice as narrow as that 16T5, but it would have an eye relief of 5mm, and no one would find that comfortable for a 82° AFOV eyepiece (God knows how many people complain about the eye relief of the 16T5, even though I love it).
Since the larger Meade 5000 UWA that later became the ES 82° were --ahem-- 'inspired' by the T5 Nagler (a range which goes from 16 to 31mm, with the 30mm a direct competitor to the Holy Handgrenade aka 31T5) you can see where they started to adopt a more or less roughly scaled design.
Edited by sixela, 22 June 2021 - 11:36 AM.