Rather than look at it as the value going up or down, you should look at it as Storj Labs forcing you to invest in the token or not.
The way it works now, you always get paid exactly what you’re owed in USD. Which is a stable currency. You don’t have to take on any token fluctuation risks if you don’t want to. But if you do, you’re still free to buy tokens yourself.
Now if it were the other way around and Storj Labs would hold back the tokens in Storj amounts, you would be forced to take on the token market risks until payout and there is nothing you can do about that.
Even if you wouldn’t complain if the value goes down, others will. And they would have a much more legitimate claim about being wronged, because they would have no way to avoid the market risk, while you currently have every option to take that on if you want.