I read the environments documentation here and the issues opened under the environment resource, however I find it impossible to achieve my goal:

I would like to use a parametrized yaml template in order to deploy to multiple environments like below:

parameters:
  pool_name: ''
  aks_namespace: ''
  environment: ''

jobs:
  - job: preDeploy
    displayName: preDeploy
    pool:
      name: $(pool_name)
    steps:
      - template: cd_step_prerequisites.yml


  - deployment: Deploy
    displayName: Deploy
    dependsOn: preDeploy
    condition: succeeded()
    variables:
      secret_name: acrecret
    pool:
      name: dockerAgents
    **environment: '$(environment).$(aks_namespace)'**
    strategy:
      runOnce:
        deploy:
          steps:
          - template: cd_step_aks_deploy.yml


  - job: postDeploy
    displayName: postDeploy
    dependsOn: Deploy
    condition: succeeded()
    pool:
      name: $(pool_name)
    steps:
      - template: cd_step_postrequisites.yml

I would like to use this approach so that I only host a minimal pipeline.yml next to my code, and then I would have all the templates in a different repo and call them from the main pipeline, as such:

resources:
  repositories:
    - repository: self
    - repository: devops
      type: git
      name: devops

  - stage: CD1
    displayName: Deploy to Alpha
    jobs:
      **- template: pipeline/cd_job_api.yml@devops**
        parameters:
          pool_name: $(pool_name)
          aks_namespace: $(aks_namespace)
          app_name: $(app_name)
          app_image_full_name: $(app_image_full_name)
          environment: alpha

Then I would be able to pass the $environment variable in order to manipulate multiple deployment targets (AKS clusters/ groups of namespaces) from one template. Currently this seems to be impossible as the default AzureDevOps parser fails when I try to run my pipeline, with the message "$(environment) environment does not contain x namespace" which tells me that the variable doesn't get expanded.

Is this planning to be implemented anytime soon? If not, are there any alternatives to use only one parametrized job template to deploy to multiple environments?