Implying research today is anywhere close to research of the past. The amount of capital and complexity to do fundamental research far eclipses what was required in the past.
This is absolutely the reason. So much was unknown at the time that a huge chunk of inventions and discoveries were completely accidental. There's no way a young adult can build a particle accelerator and play with it in his basement and discover something new. But countless people did it in the past with chemicals, electricity, pendulums, optical devices, and mechanical contraptions.