What exactly you think is wrong with my reasoning? Just throwing a PhD around gets you nowhere with me, you might as well invoke some Pokemon cards. "Gain of Function" experiments involve viral particles that sometimes aren't even infectious to actual living hosts any more, hard to believe they are viable as "practical" diseases.
In my practical understanding, maybe you have some new groundbreaking and unpublished methods of inventing completely novel but extremely viable viruses from scratch, laboratories have to take in a virus before they leak it. That's still the part of the "lab leak hypothesis" that is the sketchiest. Sars-CoV-2 has no known remotely immediate ancestors in any database. Meaning the supposed laboratory X had to do everything in secret before they knew it had to be kept secret. And there was some secrecy after the fact, but the typical Chinese face saving idiocy doesn't buy you the liberty to claim anything you want. Also there is no "designing" of diseases without a sophisticated and large scale industrial process, and it's hard to believe China would chose anything like SARS-CoV-2 for that... There have been some experiments around making a virus more adapted to one host species or integrating some novel proteins. That's about it. All the experiments concentrate on single aspects of a virus because evolving a complete virus is just so combinatorically complex (and pointlessly dangerous). If a lab passes a bat virus through Human cell cultures, yes, it gets more adapted to Human cell cultures, but less virulent. Most genetic manipulation will also result in a virus that loses lots of its function. It is virtually inconceivable that a lab takes in a virus that is incapable of infecting Humans (or causing a pandemic) and then leaks a virus that is capable of infecting Humans and causing a pandemic. There is nothing in that lab selecting the particles for their "pandemic potential", and we know that "pandemic potential" is a trait that virus rarely achieve.
If Sars-Cov-2 DID "leak" from a lab, my opinion is that it did so without any intentional modifications. And then there would still be the question where did they find it and when would it have reached Humans without help.
In my practical understanding, maybe you have some new groundbreaking and unpublished methods of inventing completely novel but extremely viable viruses from scratch, laboratories have to take in a virus before they leak it. That's still the part of the "lab leak hypothesis" that is the sketchiest. Sars-CoV-2 has no known remotely immediate ancestors in any database. Meaning the supposed laboratory X had to do everything in secret before they knew it had to be kept secret. And there was some secrecy after the fact, but the typical Chinese face saving idiocy doesn't buy you the liberty to claim anything you want. Also there is no "designing" of diseases without a sophisticated and large scale industrial process, and it's hard to believe China would chose anything like SARS-CoV-2 for that... There have been some experiments around making a virus more adapted to one host species or integrating some novel proteins. That's about it. All the experiments concentrate on single aspects of a virus because evolving a complete virus is just so combinatorically complex (and pointlessly dangerous). If a lab passes a bat virus through Human cell cultures, yes, it gets more adapted to Human cell cultures, but less virulent. Most genetic manipulation will also result in a virus that loses lots of its function. It is virtually inconceivable that a lab takes in a virus that is incapable of infecting Humans (or causing a pandemic) and then leaks a virus that is capable of infecting Humans and causing a pandemic. There is nothing in that lab selecting the particles for their "pandemic potential", and we know that "pandemic potential" is a trait that virus rarely achieve.
If Sars-Cov-2 DID "leak" from a lab, my opinion is that it did so without any intentional modifications. And then there would still be the question where did they find it and when would it have reached Humans without help.