Betteridge's law of headlines be damned, the answer is "yes". I've basically only used Duolingo for learning a particular new language. I started from nothing, and just did a little every day during the pandemic. Then I travelled to the country in question, and was able to tell stories in the language. Not easily, and with bad grammar and my vocabulary sucked, but this is more than being able to order at a restaurant…
by my experience when these people see you don't understand, they think speaking louder will make you understand