For many years, fusion reactors also experienced exponential growth in a key progress/performance indicator: https://www.google.com/search?q=fusion+progress&so

For many years, fusion reactors also experienced exponential growth in a key progress/performance indicator: https://www.google.com/search?q=fusion+progress&source=lnms&tbm=isch&sa=X&ved=0ahUKEwju4t-fr_LQAhUN6WMKHdeeCAYQ_AUICSgC&biw=614&bih=308#imgrc=tNeqSdatKNPh4M%3A https://www.google.com/search?q=fusion+progress&source=lnms&... I would encourage humility when considering whether to make a claim about a field that you are not well informed of. Real progress is being made, by a number of different groups, in a number of different directions.