You mentioned high-temperature superconductors. After 30+ years, there still isn’t a successful theory for them. However, there are some applications that have been successfully developed (technically at least, although not in the business sense.
Is that a reasonable comparison, IO?
How much has been spent on HTSC? (The estimates for CF / LENR are $50 to $100 million last time I looked). IBM alone has spent $100 million on HTSC.... and it is far easier to show the sine qua non HTSC endpoint, that is the Meissner effect, than it is to show some (currently) modest "excess of chemical" energy using calorimetry for CF /LENR
How much negative "attitude" toward HTSC has been shown by Scientific American, Nature, mainstream media? Virtually none. Ironically few physics and/ or no electrochemically-trained personnel (Shanahan?) have ever been involved in setting the demonstrably negative media "attitudes" with respect to CF / LENR.
How easy is it to demonstrate HTSC works? (I personally have easily shown it works via Meissner repulsion at LN2 temperature.) in other words much, much easier than CF / LENR.
I suspect the huge vested financial and professional interests in "hot fusion" has been responsible for much of this difficulty with funding and "attitude". Coupled with the relative technical difficulty in clearly demonstrating the CF / LENR effects... Whether thermodynamic or the modest levels of expected (from high energy collisional research) fusion products / by-products.