Including some VERY BIG ideas that we don’t yet have.
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The 1890’s were about 10-20 years before Einstein’s work. It seems to me I’ve read articles that suggested that scientists of the day were seeing too many things that didn’t fit the then standard model. So they thought a paradigms shift was just over the horizon. And so it was.
Do you see a paradigm shift coming in the nest 10—20 years.
In doing so, they created a problem, because you see, it was known that there was an enormous disconnect between the known properties of the electromagnetic force, and Newton's Laws of classical physics.
The problem, in a nutshell, is that Maxwell's equations were already Lorentz Invariant: they already obeyed the Special Theory of Relativity ... 41 years before Einstein!
And so it was known we needed to reconcile these two things because both appeared to work in the cases where you could keep them separate. That is very much analogous to what we have today, where you have this tremendously successful theory of Quantum Mechanics/Quantum Field Theory on one hand and General Relativity on the other. And, as was the case before, they can't both be correct [and it's pretty clear that it's General Relativity that has to be wrong.]
The difference now, unlike then, is that in the late 19th and early 20th century people were doing all kinds of cool things with electronics, electromagnets, motors, generators, radio waves, ... probing deeper and deeper. We can't to that now, because the energies we can reach in our accelerators are many orders of magnitude too small for us to really investigate things. We have the theories, but we don't have the experiments. [It took us a really long time to reach the energies we needed to find the Higgs, for example. The next levels we need to reach are so much higher.]
Now, there is some hope, and that hope is in space. Because the energies we need to reach that we can't reach in our labs existed once: in the 10-30 or so seconds right after the instant of creation.
So it may be possible that we can reason some of things these backwards from what we see in the sky. Not just reasoning from cosmology, but also in the so called "cosmic rays" which bombard the top of our atmosphere. These are really tremendously energetic γ rays [some are powerful enough to spawn particles in the range to test some theories that we can't test on earth.]
But it's going -- just in my opinion -- to take a lot of work, and I don't think that 10-20 years is enough.