It's called SHITTY genetics and I won't let anyone tell you otherwise. The seed breeders still havent got it down but they will tell you that they do. They will also let you believe that if you're plant isn't picture perfect its got to be something that YOU did because they are (of course ) perfect. I've personally have had better bagseed plants than any shit I've gotten from breeders. Your plant is to young to be zink deficient or deficient in anything really. Unless you are growing in straight sand or perlite this is not your problem. I've started many, many seeds in my lifetime. Seeds of all sorts for that matter. Some seedlings are weak from the start and those seeds are culled by farmers.This is no different. I currently have some nice looking seedlings in standby preparing for the big lights. All are growing beautifully except 3. They ALL get the exact same treatment and they are all grown in the same soil. Check it out. 1 popped open and when the first leaves opened they had deformed sun burnt looking spots. This was not from nutrients, light or water. Look at the 2 nd "shrimp" I call it. It sprouted and didn't do shit. The 3rd , look at those wonky ass leaves. If they were radishes I would pull them up and start over. But since they aren't , I'm going to just let them do whatever.
There is some very real in that. Not every seed you pop is going to be a prized specimen. Like not all animals are born perfect. Or humans. That's just life.
I once culled a top seller. It looked ok, but it was the runt from hell. After about a month I just decided it wasn't worth the effort. It was a single pick and mix so, I don't really blame the breeder or the strain. I had no others of this strain to compare it with. It was just my turn to draw the short straw so I simply let it go. If it were my only seed and I had no other options I would have grown it out. Every other journal I've seen on this gene the plants looked great. So. Stuff happens. My turn. I could probably bitch and maybe get a replacement. But that don't seem worth my time and efforts either. Moving on.
Your little runt. I had one of those too. The cotyledons didn't do right. It had like 1.5 and the .5 was all burnt up on the half tip. Then the first couple of true leaves looked retarded very similar to yours. Even the first fan leaves had like 2 and 4 leaves. It took maybe a month to get 4" high. I didn't have any more seeds so, I let it go. After about a month everything started looking normal. Eventually you couldn't tell it had ever been a runt. It probably took a month longer than it should have but, eventually it looked like what you would expect. It became a really beautiful normal looking plant. And the product and yield was fantastic. Actually to be expected from this reputable breeder, which I have fantastic results using them almost every time.
So I agree with you to a certain extent. I think your plant could do like mine. It looks very similar tho I remember mine looked worse. Or maybe it won't and should be culled. Never know until you try. Maybe it's not worth your time to try like that other I finally culled. Or you don't have space. We should also consider that is why some commercial farmers clone. It isolates the variables somewhat.
Anyway. Good stuff man. Life is like a box of chocolates. We're all just rolling the dice. Some luckier than others I suppose.