Thankfully Pulumi[0] allows me to write Terraform configuration in a language I know without reinventing the wheel. It feels like Pulumi's approach is better in every single way I can imagine. I simply do not see the reason for HCL whatsoever.
What about the poor support for defaults and partial overrides on object-type (read: namespaced without redundant_underscore_thing_*) configuration directives?
What about the very limited module capabilities?
What about the limited set of deterministic functions available (e.g. you get base64, yaml, csv, and otherwise GLHF)?
HCL is its own language so Hashicorp can "own" the experience, tie you into an Enterprise toolchain, and scratch their "I've always wanted to build a language!" itch
But it works and ops people love it because most ops people in industry today cannot even write a simple Python script. So...tools like Pulumi are actually out of their reach.