>>149330783
Don't forget
>If you drink the Getafix's healing elixir and magic potion in short succession, unpredictable side effects will occur (The great divide)
>If you mess around with magic potion ingredients without knowing what you're doing, you'll also get unpredictable end results (The big fight)
It seems like it's a temperamental potion and it's difficult to get it just right.

The movie where Getafix tries to find an apprentice also addressed why the villagers don't simply share the magic potion with all the other Gauls and liberate their homeland from Romans. They fear that sharing the potion across Gaul would be much like opening Pandora's box. If the potion was shared, it would be far more easy for bad actors to obtain it and abuse it.

Getafix doesn't seem openly pessimistic to me. However, he has acknowledged that time changes and things don't stay the same. He seems to privately believe that the village will inevitably succumb some day in the future, whether it's to Rome or some future trouble.