There is an opportunity here for Amazon to take some of this goodwill IBM/Red Hat is losing. Make Amazon Linux run nicely outside of AWS with (free) LTS. Charge for support for those who need it.
When Oracle messed with Java LTS AWS did Corretto LTS. When Elastic did Elasticsearch license change, Amazon/AWS did Opensearch.
They don't need to support esoteric hardware (at least other than their own).
Yeah, I would think functional/function-based indexes should be mentioned. Add an index or add a redundant column? Almost all of time I would prefer the index.
Of course if your database can't be changed then maybe you can use this trick if there is already a suitable indexed column.
https://github.com/ben-manes/caffeine