Ecofascism has the power to go the extreme when it comes to the actions people might take to protect the environment. Citizens must be protected by the government against people who, for example, wish to blow up the homes of powerful coal or fracking industrialists. Without protection against ecofascists, everyday citizens can die from terrorisitic activities.
Yes, ecofascism is a legitimate movement that we should be concerned about, because terrorism and bullying is a problem in all of its forms. Ecofascism can make groceries like fruits and vegetables more expensive, because farmers have to comply with a lot of costly rules. Ecofascism can deny people freedom of choice. There are a lot of things to be concerned about.
No, we should not worry that ecofascism is a legitimate movement that we need to worry at all about. It is just an idea or thought that people think is occurring, but in all reality it is not ever going to take off and be a big problem for anyone.
Notice most accusations of ecofascism come from fringe members of their respective parties, it's rarely a talking point for people that aren't controversial by nature. There is a minor ecofascism movement that wants to regulate population amongst other things but it's by no means legitimate nor a movement that is ever going to be within striking distance of being able to make decisions.
Change doesn't happen in groups or at the highest levels of government. No one should worry about ecofascism because changes happen at home with parents and children. If humanity moves towards more eco-friendly policies, that will happen when our children embrace such concepts readily because they are educated. Ecofascism is just a minor fad that doesn't have to be so gung-ho about climate change.