Hive Metastore Caching is disabled in the Iceberg connector.
https://github.com/trinodb/trino/blob/master/plugin/trino-iceberg/src/main/java/io/trino/plugin/iceberg/catalog/IcebergCatalogModule.java#L69-L78

Though the Iceberg table doesn't store information like the table's partition, if the list of tables itself is large (in 1000s) then calls like show tables or queries for system.jdbc.tables table to get all the tables from all the schemas across all of the catalog/connectors can also result in listing tables.

Calls to get metadata/tables can be quite frequent from the SQL Editors/DBeaver or applications which are also showing/using metadata.
So, if we cache this data in Trino, then can avoid fetching it all the time from HMS for every request from the clients.