My PhD was mainly focused on microscopy. I'd say yes and no - we are definitely heading towards the realm of dimnishing results with most microscopy techniques

My PhD was mainly focused on microscopy. I'd say yes and no - we are definitely heading towards the realm of dimnishing results with most microscopy techniques (cryo electron microscopy is an exception which is being used to understand protein structure, though id argue it's only important because we still don't have the computational ability to solve a protein structure given its sequence even though it's pure chemistry). The field of connectomics is also exciting in this regard. However, I'm more hopeful for future versions of microscopes which are not even in the realm of imagination of current researchers (an MRI microscope with micron resolution? Yes please!)