I will just say hands up or not, which they are (due to stalemate) I was going off a detailing world official forum testers that has used the product in many different applications and found that spreading the product not only used less but achieved best results as did most regular users of the product. Other than your word, still no demonstrated working example of spreading the product on a wet panel being detrimental to longevity. Not once have I said applying dry is a good idea and even the videos says it isn't however was answering a question towards this poor method.
https://detailingworld.co.uk/forum/showthread.php?t=410702
Ive neither purchased megs or gyeon wet spray sealants, so don't feel passionate towards either. Personally Im much more concerned towards users real world best usage of any given product, rather than the manufacturer label. If both methods happen to coincide, fab - if not that's life. How often do we hear of a manufacturer releasing a product, listening to user feedback and adjusting the product accordingly. This is common place and appears correct to do. Meaning it isn't a given that the label is always best practice. From the detailing world thread it would appear most uses that had posted preference is the wet spread, which makes sense given the product usage and coverage.
Shall we all get back to topping up our lockdown tans?