Why are two versions of bikinGreen 46/30 chainrings quite different?

Tech
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In 2020 I bought bikinGreen 46/30 chainrings, designed to fit on 5-bolt 110mm BCD that would normally fit a 34t chainring at the smallest. The bikinGreen setup works by some offset and smaller chainring bolts that thread directly into the inner ring.

Recently I bought two more sets of the chainrings. All purchases have been on eBay. But I just realized the two recently-purchased chainrings are somewhat different than the rings I bought in 2020. I’m curious why. There are cosmetic/aesthetic differences, but I’m more curious about

a) the older style had about 8mm spacing between the outer and inner ring, and the newer style is about 10mm

b) the newer style has more slope/overhang on the backside of the big ring, perhaps to keep a narrow chain from getting stuck in the wider gap between chainrings

I can of course trial-and-error, but I’m curious if there are reasons for these changes, and how they interact with different drivetrain setups (particularly chain width, but also the chainring spacing working with brifters).

Older chainring shape (top pics) and newer chainring shape (bottom pics):

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Newer, wider-spaced chainrings (left, silver) and older chainrings (right, black):

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This isn’t a commonly-reviewed brand, and despite being around for awhile (and bikinGreen.com being printed on the newer chainrings) doesn’t seem to have a website. Strictly (re)sellers online, mainly eBay, as far as I can tell. But hopefully some folks here are familiar with them.

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The silver rings with the wider set and essentially wider ramping more closely mimics what Shimano has been doing since the Dura Ace 7900 generation. Among other things, it reduces the chance of dropping the chain when shifting from the big ring to the small ring.

As chains got narrower, the gap between chainrings had to shrink. Otherwise, the chain could jam between the rings, or more commonly the chain would ride on top of the teeth of the small ring without engaging. The consequence of this narrowing was that it became easier for the chain to miss the inner ring entirely when shifting off of the big ring. Shimano finally figured out that the chainring TEETH could be wide set, as long as something filled the space. I feel that the ramping could improve as well, as there was more real estate to work with. Lastly, it allowed for a little more room to cross chain in the small ring.

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Thanks Gregory! That all makes sense - you could keep moving chainrings closer together so chains don’t get stuck, but then you rub the big-ring teeth when cross-chaining in the small ring.

Sounds like the newer style will work fine with wider and narrower chains, but the older style will be a problem with 11s (or narrower) chains. I’ll use my older-style rings on a 9-speed bike, and the newer-style black rings on an 11-speed bike I’m building up. The silver newer-style is my wife’s road bike (9-speed for now) that she wanted with all-silver components.