While not perfect, `terraform plan` is a massive time saver. A lot of IaC tools still don't have good (or any) support for "dry runs" and provisioning a bunch of infrastructure to see if your thing works is really slow
100%, `terraform plan` is such a useful time and cost saving step when developing terraform.
Ive read about pulumi and casually used it (python) to learn about it. Benefits like taking advantage of proper python language niceties, like running pytest on your IaC.
Additionally, it uses terraform's providers behind the scene, both contributing their success to the other.