TL;DR: you now need to pay a $20/month "meta premium" subscription to use a 100% offline feature that runs on your own malware-ridden smartglasses.

If you don't subscribe, you can use the feature that is already included in the hardware that you already paid for 3 hours each month

The now-paywalled feature boosts the voice of the speaker in front of you, something that even low-end ANC earphones are doing now. 5 minutes of free usage per day is basically nothing.