Those crazy price predictions will only happen if dollar is affected by a very high inflation. It would not be bitcoin increasing its value, but dollar losing it. At this point, some other pair would be used against BTC, some other fiat or even gold (?)
Why so pessimistic? There's possibility Bitcoin price going to the moon either because mass adaption or legalization on big country.
By then, people would feel Bitcoin transaction fee is expensive, even though it fees on Bitcoin is unchanged.