Automation is not only related to the speed of setting up infrastructure. Don’t forget about the 100% repeatability of automated infrastructure setup. Personally, I always try to go the extra mile in automating such setups. Earlier this week, I bumped into this tweet which aligns with my personal preference:
https://twitter.com/jpmens/status/1554752130698838016?s=21&t=bfd0hMdG90YZptsJFcy-wQ
Besides the Azure Classic and Azure Native providers, we also have an Azure Active Directory provider:
https://www.pulumi.com/registry/packages/azuread/
I don’t know how B2C deviates from standard Active Directory. It’s worth a try to see if this provider allows you to manage B2C as well.