The „geometric“ style as you call it, has also gradually disappeared here in the UK. A few square greens are left, however I believe they have been considered as a primitive form of golf course architecture.
The celebrated architects didn't use strict geometeric features and they weren't inherent on the ancient links.
I'm not familiar with the names of the golf course architects that deliberately favoured this style.
I assume the tee and green centres of these early courses were laid out by old golf pros and left to the locals to construct.
I believe these old geometric features, which could be maintained by a hand mower in earlier years, were rounded out over time to suit the turning circles of the triplexes
Of the geometric greens and golf courses I'm familiar with, one golf course, Freshwater Bay on the Isle of Wight was altered by the greenkeepers in the 80's to improve the aesthetics and to suit the turning circles and gradients of their sit-on mowers.
The other one, Corrie Golf Course on the Isle of Arran, still has what I call „gun emplacement“ greens.
They can't afford any major changes and so they remain.
Ideally the square greens should be preserved as one of the last examples of this early style of primitive golf course architecture.
I'd love to hear from the DG of other similar courses.
As far as their defence is concerned, if one is confronted with a steep corner of the embankment in the path of your chip, it certainly meant pitching over the corner rather than running it through. Generally low steep embankments surrounding the lower side of such greens made shots more difficult - however I do relish the bounce shoot into the higher banks which then land softly on the greens.
Getting stuck in the corner of a square bunker is also challenging,
Maybe a rut iron was the answer!!!