In Finland, the Greens actively and vocally opposed nuclear power at least up until recent years. They abdicated themselves from a coalition government in the early 2000's over that government's decision to grant a license for constructing an additional reactor at an existing plant. Rejecting nuclear power was definitely a visible part of their ideology. That part of the stereotype was actually true for a long time.

I don't know about Germany, but it is my impression that opposition to nuclear power was a common theme among the green movement in general for decades.

Obviously their agenda also included investing in renewables, as well as reducing consumption, but that wasn't going to happen fast enough, either for political or technological reasons.

I have voted for the local Greens several times over the last couple of decades even though I disagreed with and was frustrated with the views they held on nuclear power until recently.

I'm also unfortunately familiar with many of the common and overblown negative stereotypes towards the greens in general.

Insofar as nuclear power could have played a part in reducing our dependency on fossil fuels over the lasts couple of decades, though, I don't think it's unfair to say the greens in many countries did a lot to hinder that.