This is usually because proponents of nuclear energy are not pushing for "traditional" reactors, but for Breeder reactors.
These were the direction we were headed in the 60s, unfortunately, we then discovered that Uranium was not as rare as we thought it was, and in our usual manner, decided to go for the conventional ones we have today.
Whilst breeder reactors produce waste, they can also reuse it, as well as being more efficient. Some proponents say they would allow us to reuse today's nuclear waste.
Additionally, the waste produced has a shorter half life than the waste produced from conventional reactors.
These were the direction we were headed in the 60s, unfortunately, we then discovered that Uranium was not as rare as we thought it was, and in our usual manner, decided to go for the conventional ones we have today.
Whilst breeder reactors produce waste, they can also reuse it, as well as being more efficient. Some proponents say they would allow us to reuse today's nuclear waste. Additionally, the waste produced has a shorter half life than the waste produced from conventional reactors.