This is not correct. Snapshots in Elasticsearch are deduplicated, but logically independent, quite unlike incremental backups which depend on earlier backups.
This is not correct. When you restore an index, you restore its mapping too.
This is also not correct, for the same reason. No need to manually update any mappings.
This is also not correct, for the same reason. The restore process restores both data and mappings.
Was this answer partially written by OpsGPT like some of your earlier answers? It's very nicely written, but fundamentally incorrect.