Consider deprecating old parsers API

**Feature request**
It would be great to have encryption for models.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_encryption` with default `false`.

No files, tests, or entry points are identified. First reconcile the title about deprecating old parsers with the body’s request for model encryption, then locate the configuration and model-encryption entry points. Done means the agreed scope is implemented with `enable_encryption` defaulting to `false` and covered by relevant tests.

Written by the indexing model from the issue text.