I did mention that: But there is of course option of discovering something that we don't even imagine at this point and this could have practical implications.

I did mention that: But there is of course option of discovering something that we don't even imagine at this point and this could have practical implications. Also, I wrote "From this one could reason". I, myself, actually hope that we will get some breakthroughs, because established theories make ridiculous predictions or require equally ridiculous fine tuning. One example is vacuum catastrophe: "the worst theoretical prediction in the history of physics". We have had similar prediction in the past e.g. "ultraviolet catastrophe" that lead to the whole idea of "quantum". But IMO the issue here may be more fundamental. Testing quantum gravity theories requires energies way beyond stupidly high energies like in LHC. As I understand, the requirement follows from the theory. It's like light speed limit, it's not something you can engineer around to see in lower energies. You can engineer your way up to get these energies, but there doesn't seems to be a short cut like with positive feedback loops in case of A-bombs. Chicago Pile 1, first nuclear reactor cost 50 000$ at the time, so something below 1 million $ today. Most of historically important experiment then was even cheaper. We stumbled upon lot of things because we were doing sort of cheap random search around things we did not understand. Most importantly cheapness of these experiments coincided with potential of practical applicability. I fear that this is mostly over, because as far as I know we don't have fundamentally inexplicable phenomena, I stress "fundamentally", that we can play around with cheaply. LHC budget is somewhat around 10 billion $, JWST another 10 billion $, LIGO somewhat around 1 billion $. And as I understand this is nothing in comparison to what would be required to reject e.g. string theory. If you can't experiment with it cheaply I doubt that you can apply it cheaply.