I used to notice and somewhat - but not solely - rely on icons, especially nice designed sets.
It seems though that a combination of samey-sameness (greyscale, shape, etc...) and the constant bombarding of attention-grabbing imagery (emoji, gif, ads...) has desensitised me from visual cues and I zero in on text instead now.
I think you're right. Desensitization has to be a big factor.
I'm certain that I just _like_ text, but I've also noticed recently that I miss very large attention-grabbing print (eg. "SALE" or "FREE WIDGETS JUST GIVE US YOUR EMAIL ADDRESS") as well. I think my brain has started flagging it as misleading noise along with the rest of the detritus.
It seems though that a combination of samey-sameness (greyscale, shape, etc...) and the constant bombarding of attention-grabbing imagery (emoji, gif, ads...) has desensitised me from visual cues and I zero in on text instead now.