Physics after a century
In 1900, all physics knowledge that existed was the Newtonian and Analytic Mechanics with Thermodynamics and Maxwell's Electromagnetic equations. But it's now 2000's and a theoretical physicist has to deal with some several differential geometries, quantum field theories, early universe particle physics and cosmology. That's equal to slaughtering your mind. All Einstein did was take Minkowki's geometric approach to STR and write equations in Riemann then derive field equations. Now I'm not saying what he did was easy, but it was not easy for his time. Now even a sixteen year-old can learn differential geometry and study general relativity. But if you want to be on the same level as Einstein one gotta develop some theories in furthest geometries and spend their life maybe without achieving. Fuck no bro, it isn't that hard, you just need to be some clever.