Why would they be? Pulumi talks to providers at the protocol level - contrary to the belief of many, Pulumi is not a Terraform wrapper.
Clearly, based on my downvotes, I'm mistaken and should be ashamed.
[1]: https://www.pulumi.com/docs/using-pulumi/adopting-pulumi/mig...
Downvotes are nothing more than an indicator of how many people clicked the downvote button.
That was several years ago, though; might be stale.
There is an unfortunate meme that this makes it a “Terraform wrapper” like CDK for TF, which it does not.