Note: I'm not a native speaker.

English doesn't have genders and cases [1] so grammatical constructs such as if/then/else, case of, unless etc. suffer much less than when you have gender and case. Oh, god, and plural forms of those.

For a Russian speaker using a PL in Russian is constant pain as your brain tries to add all the missing parts to the words:

   if(count(letters<must have a plural ending, accusative case>) > limit<must have singular ending, genitive case>){
       words.append(word<must have singular ending, accusative case>)
   }

etc.

[1] Well, it does have those, but not in the same capacity as other languages.