I think you misunderstood my point.

Maybe? If you're asking how the original companies stay in business when a clone comes along, the answer to that is that many times they don't. And, as mentioned elsewhere (and maybe even here), if we're talking about tangible goods, then, in most cases, there are clear differences between the clones and the non-clones. If enough people buy the items from the original maker, then they stay in business. There are plenty of examples where clones popped up in a market and forced the original creator out of business. We're not talking about "clones" in the sense that they're close enough. We're talking about exact duplications. If someone can make an exact copy for less, then the original company would go out of business if no one paid for that product. I don't know how you could view that as anything but theft.

Stealing would be if the clone company literally stole the design of the original company and installed ransomware onto their computers so they lose access to that design.

No, you don't need the second part. Stealing it would be stealing the design of the other company and selling it. Recreating something is not the same thing as stealing it, as I've already stated.