The problem unique to folks likely to be reading here is the exponential growth that can happen in early stage start ups. The options might’ve represented 100k in value when they were granted, but grown to 1m in value by the time they vested.
If you exercise you owe ~300k in taxes. Even if you have that cash the exercised shares could become worth 0 and you’ll just be out the money.
It's like if I handed you a coin that I promise is worth one million because I will buy it from you for one million right now, except I won't buy it from you now and I don't plan on buying it from you ever in the foreseeable future, and if I do buy it from you later it won't be for one million.
I agree with you the current rules kind of suck for employees at start ups increasing in value, but framing values as just made up is overly reductive.
Good thing that nobody is forcing you to take ownership of that worthless thing then.