No, Citra was free. But the devs (same devs as Yuzu) had a Patreon where they were raking in upwards of $30k per month.

The software was free, but the Patreon gave early access to development builds. And when TOTK leaked a week or two early, the patreon’s popularity exploded because everyone suddenly wanted to be able to play the game on the most recent dev build.