Is provided fruit in-flight, then fined for bringing said fruit into the country...

This is quite common for international travel (so, this flight).

Also common are amnesty bins, excessive signage prior to the customs point, and the literal agriculture form the passenger even mentioned reading and signing, that all passengers are required to read and sign.

That’s not to say the system isn’t flawed, there may be elderly or ESL (or complete non-English speakers) or disabled folks on the flight as well.

The airline was idiotic for giving out whole fruit on any international flight. It is 100% on the airline, to be clear.

However, the same thing would have happened to anyone taking fruit/veg/meat, etc off the plane. So, almost anything they would serve besides processed snacks. Bags of jerky will net you an even larger fine flying into Taiwan.

It’s just the nature of international flight, you can’t simply bring random agriculture products across borders. Hawaii has no venomous snakes and no rabies in the entire state for a reason.