With the increasing global push for carbon neutrality, the transition to sustainable energy sources like hydrogen has become imperative. Proton Exchange Membrane Fuel Cells (PEMFCs) play a central role in the hydrogen economy by converting H2 fuel into clean energy with only water as a by-product. However, the adoption of PEMFCs is limited by the high cost and constrained availability of Pt-based catalysts necessary for the oxygen reduction reaction (ORR) at the cathode. While non-precious metal catalysts have shown progress, they still fall short of the efficiency levels of Pt-based catalysts, demanding a need for improvement in catalyst activity and a reduction in Pt loadings. Researchers have been exploring various avenues to enhance the catalytic activity of Pt, such as manipulating the size of Pt nanoparticles, alloying Pt with metals like Ni and Co, and creating unique nanostructures. Despite these advancements, challenges arise in translating high mass activity electrocatalysts into efficient catalyst layers in actual PEMFCs. Gas diffusion electrode (GDE) half-cell setups have emerged as a promising method to study catalyst properties and offer more realistic insights into catalyst stability. An essential aspect often overlooked is the interplay between the carbon support, ionomers, and catalyst in the catalyst layer, impacting the transport of oxygen, protons, and water. Nanostructured thin-film (NSTF) catalysts have been developed to eliminate the need for ionomers by directly coating Pt or Pt alloys onto crystalline organic whiskers. However, challenges like water management and proton conductivity persist with NSTF catalysts under certain conditions. Researchers are exploring strategies to optimize ionomer coverage on Pt surfaces, including chemistry modifications, molecular masking, and support engineering. Finding a balance between low and high surface area carbon supports is crucial for enhancing proton and oxygen accessibility. Continued research and innovation in catalyst technology are vital for advancing the efficiency and widespread adoption of PEMFCs in the transition towards a more sustainable energy landscape.