Replace template / inherit mechanism with standard yaml anchors?

On the topic of complex test definitions in the old way of configuring things...

Can the template/inherit keywords be replaced by simply using yaml anchors?

And similarly, say that in the future we figured out that it was possible to support 100% of configuration options also via CLI and environment variables... Then of course the same question can be asked about environment variables: Is there anything wrong if I just do the templates as a series of env vars, substituted in bash:

TEMPLATE_1=....
TEST_1=.... ${TEMPLATE_1} ....
TEST_2=.... ${TEMPLATE_1} ....
otava -arg1=foo -arg2="$TEST_2"

The overall question is, can we do all configuration without substituting environment variables into a yaml document? I'm not strongly against it, I'm just asking whether this is an unnecessary feature or whether someone can show me an example where the functionality is really needed?