I think there's a serious related issue which is that icon packs (font awesome, feather, material icons, whatever you prefer) encourage you to just pick the "closest" icon for a given menu item, rather than an icon that is actually what you want.

At work we do sometimes design custom icons for specific things, but that's very rare and relatively costly. Most developers on our team don't have that capability, and we are left trawling through Google's admittedly-large icon library to find something that seems plausible.