In this work, we directly simulate the transmission spectroscopy of coupled light-matter systems, forming excitonpolaritons, in the presence of various molecular excitation frequency disorders. We find that the transmission spectra take on drastically varied characteristics between different electronic disorder types (Gaussian, rectangular, Lorentzian) as well as between one-, two-, and many-molecule (more than 100) systems for a given disorder type. Second, the Lorentzian profile shows little-to-no modifications by varying N. Finally, our simulations reveal that the number of molecules necessary to saturate the collective effects for linear transmission spectroscopy to be N ∼ 100 or less, irrespective of the disorder type and magnitude.