Hi @jsecor-zus,
Welcome to the Auth0 Community!
Yes, the solution provided in the Post you shared is still the recommended way to set the favicon when using the New Universal Login.
AFAIK, we do not currently have any plans to support setting the favicon via the Dashboard. Generally speaking, anything that can be done through the Auth0 dashboard (and more) can also be done through this API.
Moreover, this doc explains that the New Universal Login pages can only be customized using the Management API.
I hope this addresses your questions.
Please let me know if you have any additional questions.
Thanks,
Rueben