You mean before they even announced that any car would get track mode? The first time track mode was mentioned people asked if it would be limited to Model 3s with PUP, and most people thought that it would. And then when Tesla actually announced it, they confirmed that it was limited to the Model 3s with PUP.
You can't reasonably expect Tesla to just give you anything that they release after you purchase your car just because you would have bought it had it been offered to you at the time.
I think you answered your own question then. Why didn’t someone order PUP if they wanted track mode? It wasn’t announced at the time of delivery.
I don’t think you should argue what most people thought. Looking at that twitter thread, people thought all performance versions would get it. Poor communication from Tesla is why people didn’t make better decisions. Everyone had to make the best decision they could based off little information. Hindsight is 2020.
I think you can reasonably expect all performance models to receive something if the company previously mentioned a feature and didn’t differentiate that only one add on would receive it by the time you took delivery.