You can actually give a semi-plausible justification of special relativity based on what was known in 1901. Maxwell’s equations are fundamentally incompatible with what I might call “Newtonian relativity.” They define a fixed speed for light, which is impossible in Newtonian relativity for observers in different inertial reference frames. Magnetism is also a puzzle, as the magnetism depends on the relative velocity in a way that makes it appear to create different forces in different inertial frames. Without length contraction from special relativity, magnetism has uncomfortable implications.
You can actually give a semi-plausible justification of special relativity based on what was known in 1901. Maxwell’s equations are fundamentally incompatible with what I might call “Newtonian relativity.” They define a fixed speed for light, which is impossible in Newtonian relativity for observers in different inertial reference frames. Magnetism is also a puzzle, as the magnetism depends on the relative velocity in a way that makes it appear to create different forces in different inertial frames. Without length contraction from special relativity, magnetism has uncomfortable implications.