const p = new aws.Provider(`main-provider`, {profile: profile, region: region})

am I correct in that there is no way of getting the profile/region on p?

You cannot get those values off of the provider object but you can via

aws.config.region

, etc. https://www.pulumi.com/docs/reference/pkg/nodejs/pulumi/aws/config/#region

Thanks, but I'm trying to use this in multi-account/multi-region programs which have multiple providers, I'm not sure I can get what I need from the global config.