To my knowledge, no one has used that quote from St. Francis, whether he actually said it or not, to claim that words have no value and that as long as we are acting like Christians we are okay. As far as I know, the quote has just been used to emphasize the importance of actions. To me, it has often been a reminder that sometimes, what we say is either not going to have any effect or is not going to mean much to others, if we are not also not living what we speak.
So the quote, regardless of who said it/if it was said at all, is (I believe) only emphasizing the importance of actions, not saying that we are not called to evangelize with words.
To the OP: Yes, the Catholic Church wants to convert non-Catholics (and Catholics who have not fully embraced the Catholic faith). As others have posted/hinted at, one of the primary purposes for the Church’s existence is for the evangelization of all people. Sometimes, it is hard to understand the words of the Holy Father (I’m speaking of myself here too…) and why he says what he does. And I think it’s okay to question what he means and what he is actually saying, as long as we are motivated simply by the desire for understanding and not some negative attitude. I would say to just remember, as I just mentioned, that one big reason (some would argue THE reason, and they are probably right at least in some sense) for the Church’s existence is for evangelization. It is up to each of us individually to discern, with the help of the Church and the graces we obtain through the Sacraments, how God is calling us to evangelize! We should always pray that our daily lives only serve to greater glorify God - very basically, if we are doing His will, then we are likely glorifying God and evangelizing as we are called to do.