It's a third more of a low figure, which is still... a low figure. As with shares it depends on how long a view you can afford to take, and if you come in at the top or the bottom. The USD:EUR exchange rate has actually been quite volatile in the past couple of years. It's gone from a high of over parity in October '22 to a low of .90 in spring, it's still nowhere near that peak of 14 months ago so if you'd sunk 20K in at that stage you'd be less than happy that it was only worth 18K and change six months later if you had needed to make your finances liquid then... despite any higher interest that would have offset that a little. It has varied about 10% in the last 14 months, and 20% if you go back three years. So yes, currency fluctuations are a real consideration, otherwise everyone would do it.
(I am occasionally paid in USD so I have been watching the exchange rates avidly over the past three years!)