Template sensor: using "this" variable

In 2022.5 a “this” variable was introduced:

Template entities now have a this variable available, which is a reference to the state of the template entity itself.

Check the blog article here.

Please have a look at this example:

sensor:
  - platform: template
    sensors:

      test_this_template:
        value_template: >-
          {% if is_state("input_boolean.test_boolean","on") -%}
          {{ "red" }}
          {%- else -%}
          {{ "brown" }}
          {%- endif %}
        attribute_templates:
          color: >-
            {{ states(this.entity_id) }}
        availability_template: >-
          {{ true }}

This seems to work.
But let’s compare with a bit different implementation:

        attribute_templates:
          color: >-
            {{ states("sensor.test_this_template") }}

Here the attribute’s value is defined based on the sensor’s state.
I guess that the difference is that:

1. Using “this” - using the current sensor’s state.
2. Using “sensor.test_this_template” - using the previous sensor’s state.

Although in this particular test case the results are same, I wonder is it correct to use the “this” variable.
State & attributes may change asynchronously, this may cause some problems… Probably using external sensors to define attributes or state could be more reliable in some cases.
Please correct me if I am wrong.

Test card:

type: entities
entities:
  - entity: input_boolean.test_boolean
    name: red color
  - type: section
    label: sensor with "this"
  - entity: sensor.test_this_template
    name: state
  - type: attribute
    entity: sensor.test_this_template
    attribute: color
    name: '"color" attribute'
  - type: section
    label: sensor with entity_id
  - entity: sensor.test_this_template_2
    name: state
  - type: attribute
    entity: sensor.test_this_template_2
    attribute: color
    name: '"color" attribute'

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