I think it might be a Swing thing. Large diameter bowls -
by that I mean 24 or more inches in diameter - require
a greater distance from between centers to the lathe's
ways. And you need to deduct some from that dimension
to the tool rest banjo. Machinist lathes - that you can
actually fit in an amateur/hobbiest "shop" just don't have
that sized swing.

The other issue is hollowing in from the end. If you've
spent any time at all leaning over the lathe doing
hollowing you soon learn that supporting your upper
body weight with your lower back almost guarantees
some Chiropractor an income enhancement, or some
time on the couch with either a heating pad or an ice
pack. Add leaning over farther to see inside the
piece and the problem gets worse - in a hurry. Long
lathe beds only add further to the leaning problem.

Now some lathe makers got around part of that Lean
Over Work problem by providing the option of turning
the drive end part 90 or 180 degrees - for "outboard
turning". That solution however, requires some way
to support the tool rest. Swing out arms attached
to the lathe's base has been one solution. Others
have come up with a stand alone stand to hold the
tool rest. Neither solution is as good as the one
Stubby came up with - the three ways positions options
PLUS the ability to rotate their answer to the normal
banjo to support the tool rest.

The Stubby significantly reduces the leaning over
problem - adjustable center height, short bed when
you need it, longer when you need that, and multiple
solid locations for supporting the tool rest.

While the OneWay addresses some of these "challenges"
it's center height is fixed and there's no way to mount
a solid tool rest support at 90s to the long axis.

Metal lathes just don't have the flexibility of this type
of special lathes.

charlie b