How this will play out is anybody’s guess, since long-term reliability is somewhat of a guessing game based on an extrapolation of models and limited field tests, particularly when it comes to new materials. Almost all PV module suppliers offer 20-25 year warranties but nobody really knows how panels will withstand the test of time. Corrosion can creep in, plastics can yellow, dopants can move and electromigration can lead to increases in line resistance. Many PV proponents believe solar farms being installed today will live on in perpetuity, since the world will always need power and the sun will always shine, but materials do tend to wear out.
Maybe bankers can intuit the viability of given technology better than expert physicists, but I suspect their questions of bankability will only be answered by reams and reams of data which they are ill-prepared to decipher.