I'm reasonably sure USD (or EUR) will still exist, have some reasonably similar value, and be usable in five years. There are quite a lot of crypto tokens I do not have anywhere near that level of confidence in.
Sure, but even with an inflation rate of 2%, if you hold USD for 10 years, its purchasing power is cut in half.
Every BAT token that’s ever going to exist has already been minted, so it can’t be inflated by creating more of it. There will be no quantitive easing, “too big to fail” or bailouts in the BAT ecosystem.
That almost certainly will not be the case for either the dollar or the Euro.
So what will be the purchasing power of BAT in 10 years?
Given that there’s no doubt there will be at least one financial crash with the dollar and other fiat currencies, there’s a more than decent chance BAT will outperform the dollar in the next 10 years, which frankly, wouldn't be too difficult.
Nothing stop you from exchanging it as soon as you can.
If the website would be offering USD instead of BAT, you would still not be able to retrieve it until it reach a amount big enough to take out (Google Ads is at 100$, 25$ for international user on Patreon). Until it's actual USD in your bank account, it's not better than BAT and depends on the existence of the service. The difference is that BAT, you can still use it if you decide to, right now.