Plenty of tool companies “copy” the successful designs from other manufacturers.
Sometimes this is just to offer their customers tools that are as functional as possible.
Other times, it’s because the customers associate “the look and aesthetics” of the tool, as part of the functionality, and the copying manufacturer wants to sell the tools they make.
Record , (and I think Eclipse), tried redesigning their tools in the 1960s? using “modern design” aesthetics, possibly as a selling ploy, or because they thought a “modern design” might be better.
It might have actually been a top UK industrial designer who did the designs, although that’s a bit of guesswork.
The planes routinely get crapped on as bad tool design, and I think Record went back to the older designs for the items they kept in production.
I believe many if the Eclipse designs remained in production.
Veritas/Lee Valley, has tried similar “modernization” with various woodworking tools such as planes, usually with less complaints, but still with some, even in major woodworking magazines.
As far as the items Harbor Freight has “copied”, many were basic tool forms that existed for decades, or even a century, that lots of people associate with Snap-On, simply because they’re the “big name” in professional automotive tools.
The Harbor Freight Icon screwdrivers do appear very similar to the Snap-On screwdrivers, but even without the branding differences, the screwdrivers aren’t identical, and the Snap-On screwdriver handle had a design patent, which ran out, so anyone is legally free to copy the design now except for the Snap-On trademarked branding.
The long nose three pivot point “talon grip” pliers were literally just a revamp of an older style of pliers, that Sears, and other manufacturers had variously offered, combined with an offset three point slip joint design, which Snap-On tried Patenting.
Snap-On used that three point offset design on a non-spectacular, fairly standard slip joint plier design, which HF/Icon copied first, and Snap-On seems to have never challenged HF for Patent infringement, either considering a court challenge not worth the cost, or maybe they sent a challenge letter, and HF pointed out why they thought the Patent was bullsh!t, so Snap-On shrugged and let things be.
Whatever the case, the Snap-On patent is likely basically unenforceable nowadays.
As far as other Snap-On pliers, many of the designs far predate Snap-On offering pliers, or even Snap-On existing.
The red cushy plier handles are hardly unique to Snap-On.
One could also argue that the Dodge Viper was built for “posers”, but that didn’t seem to stop the cars from having decent performance.