@Ashwin_s, there is just so much misinformation here, it is hard to know what to start with. Science is credible and this is not merely about “the guild.”
Psychology is on the fringes of “science”, and not at all comparable to the rigor we find in science. The cancer biology figure is widely misreported. It is about translatability, not reproducibility. These are very different things.
Many things have a falsifiability problem because, as we have covered before, there are many things outside the streetlight (Ockham’s Razor and Reality). Popper’s falsifiability has is not a coherent guide for science, in part because it is a relative term. First off “string theory” is not a single theory, but a collection of hypothesis. They are regularly ruling out classes of theories. As experimentalists like @dga471 make progress, they will rule out more. Of course we need scientists carefully formulating what specific hypothesis would entail or not. That is a valid effort.
Science does have continually improving standards of how claims are analyzed. Why in the world would you think any thing different?
They are credible because good scientists are good at identifying good reproducible work. Important findings are also verified by reproducing them.
Or maybe, just maybe, science is complex, beautiful, and sprawling enterprise that will take a lifetime to engage and understand.