That depends, how do you quantify progress or rate of progress in physics? To compare directly to technology, Moore's law seems to indicate a accelerating pace of technology. On the other hand looking back to the 90ies progress in computer games, where you could expect a never seen before breakthrough each year, it seems that computers have hit a point of diminishing returns and probably the important metric is something like the log of computing power or something similar. So quantifying rate of progress is not well defined and it seems that it is possible to argue that the rate of progress has slowed down, even for computing power. The counter example would be digital video, where there was very little progress, for the average user, until divX and since the early two thousands, we went from cut scenes at 320x240, to Youtube and 4K video.
Putting the measurement problems aside, progress in physics seems to be a lot less smooth and the big jump occurred in the first three decades of the last century with the discovery of special relativity and quantum mechanics plus the ongoing project of formalizing physics. That one was a complete paradigm shift towards mathematical models and towards an entirely different picture of reality. Since then the development of quantum field theories is basically just using the same trick as for quantum mechanics. ( Not trying to belittle the development of QFT, that is one of the monumental achievements of the human mind, it just pales in comparison to the development of QM. ) So, in this view the next big jump may be just around the corner or not possible for a human brain, but we will only know the answer after progress happened. ( I should cite one of the famous philosophers of science here, unfortunately I forgot which one.)
As an example, string theory is currently not even wrong, because we can not build the known experiments that would enable us to test string theory. However a lot of brain power and ink was expended on its development over the last thirty years, and we simply do not have a good idea if it was worthwhile. If someone suggests a experiment that can distinguish between string theory and other models of quantum gravity, and if a string theory passes this test, then it was probably worthwhile to spend all that effort.
In conclusion, I would argue that the question is ill defined and runs furthermore in epistemological problems, that is even if we would find a good definition we can not really know the answer. However, I am actually quite optimistic that a breakthrough is just around the corner. For example, I think that the connection of information theory and physics is not really understood, but concepts like entropy and information seem to crop up everywhere one looks.
Putting the measurement problems aside, progress in physics seems to be a lot less smooth and the big jump occurred in the first three decades of the last century with the discovery of special relativity and quantum mechanics plus the ongoing project of formalizing physics. That one was a complete paradigm shift towards mathematical models and towards an entirely different picture of reality. Since then the development of quantum field theories is basically just using the same trick as for quantum mechanics. ( Not trying to belittle the development of QFT, that is one of the monumental achievements of the human mind, it just pales in comparison to the development of QM. ) So, in this view the next big jump may be just around the corner or not possible for a human brain, but we will only know the answer after progress happened. ( I should cite one of the famous philosophers of science here, unfortunately I forgot which one.)
As an example, string theory is currently not even wrong, because we can not build the known experiments that would enable us to test string theory. However a lot of brain power and ink was expended on its development over the last thirty years, and we simply do not have a good idea if it was worthwhile. If someone suggests a experiment that can distinguish between string theory and other models of quantum gravity, and if a string theory passes this test, then it was probably worthwhile to spend all that effort.
In conclusion, I would argue that the question is ill defined and runs furthermore in epistemological problems, that is even if we would find a good definition we can not really know the answer. However, I am actually quite optimistic that a breakthrough is just around the corner. For example, I think that the connection of information theory and physics is not really understood, but concepts like entropy and information seem to crop up everywhere one looks.