How effective is the scientific method?

Since roughly the mid-twentieth century, most people in society as a whole have perceived certain failures in the progress of science as a whole. Most conspicuously, I would cite three particular problems. For about seventy-five years now, the limitless clean power of controlled nuclear fusion has just been "ten or twenty years away". And, it still is, "ten or twenty years away". Now, apologists will counter that the only real problem is that fusion requires more power to produce than it generates. Yes indeed, that is a problem. And, it's far from clear when it will be solved. Since the nineteen-nineties, "climate science" has been making apocalyptic predictions of global catastrophe based on greenhouse gas emissions and global warming. Many have claimed that cyclical variations in climate are a normal aspect of the environment. So far, the only apparent practical consequence is cynical shrewd opportunists like Elon Musk using "climate science" as a marketing platform to become fabulously wealthy. And, of course, the current COVID "pandemic" is making a great many people wonder very much whether government in general, and the entire health care industry in particular, really know at all which end is up. So, I was wondering, from a philosophical point of view, just how effective is the scientific method? And, is there any way of making science more effective, in general?