You ask about obstacles to progression, one of the great obstacles to progression is that we are moving increasingly away from an arena where our intuition is helpful. Another obstacle related to the first is that, in order to make progress, we have to study the behavior of matter under extraordinary conditions, because these are the conditions in which we can test our theories and which will suggest new theories. And it is getting difficult for scientists to convince governments that they should support this work. But as time goes on, these things inevitably become more expensive and that may be the most important obstacle of all. It may be that before we run out of ideas or inspiration, we will simply run out of money.
Some people talk of the end of science.
I don't think we are facing an end at all. The one thing that could cause an end of science is if the public became hostile to science and refused to support it because, of course, it can't be done without public support. It can't be done just on the basis of companies that want to make profit. It has to receive a lot of support from governments. If that stopped, that could end science for our time, but I don't think that's likely.