Hello, There is nothing wrong with using "any" with uncountable nouns as in your first and second sentence. For your third sentence, it means "there is a little traffic, not much". For the fourth sentence, people generally have one home or one job. That's why; it would sound great if you said "I didn't have a home or a job at that time". But still "any homes" or "any jobs" would make sense. With countable nouns, the choice between "any" or "a" sort of depends on how many of them you are supposed to have. For example; people are supposed to have more than one friend so we would say "I don't have any friends". Hope this helps!

There isn't any traffic. (CORRECT) There isn't any bread in the refrigerator. (CORRECT) There isn't much traffic. (CORRECT) I didn't have any home. (INCORRECT) I didn't have any jobs.(INCORRECT): CORRECTIONS: I didn't have a home. I didn't have a job.