Should you prioritise FLUENCY over ACCURACY ?

Here's a thought: The single biggest thing holding learners back is the fear of making mistakes.

We spend so much time memorizing grammar rules that we freeze in real conversations. Isn't it better to speak a lot and make 20 grammar mistakes (but be understood) than to say one "perfect" sentence every five minutes?

I believe massive output and building conversational speed is the only way. The grammar correction can come later.

Do you agree? Or do you think building a perfect grammar foundation first is the only way to avoid permanent, "fossilized" errors?