Sure, some amount of money is just the brand name. Let’s put that aside.
There is definitely a difference in quality between a $2000 watch and a $6000 watch. However, that $4000 difference is going to be far less than the difference between a $200 watch and a $2000 watch.
When goods start to be manufactured at a higher standard of quality, the costs begin to increase exponentially. You see this in every sector from watches to computers, guns, cars, trucks, furniture, clothing, etc. The skill, talent, labor, and investment to get a good from 1 to 90 is going to be a fraction of the same to get that good from 90 to 100.
And of course, as the standard of quality increases, the more experience and knowledge is required on the consumer end to appreciate it.
It’s certainly plausible and I’m sure there’s a number of people who can make good money off it. However if you’re not a collector and expert already you’re probably going to lose a lot of money if you’re trying to make a profit.