If Safari can't make a secure connection, it displays a "This Connection Is Not Secure" dialog in which you can choose to continue to the site anyhow (basically ignoring the SSL cert).
This actually might be an Apple bug- https://discussions.apple.com/thread/256142477 - I worked around this by allowing Safari to skip https to connect.
While I've had worthwhile improvements from adding a Denafrips Iris 12th DDC between my Zen Mk III and Denafrips Pontus II I wouldn't attribute it to the interface (I2S) too much- power and cabling make significant improvements, too.