Price is the only main reason I see which drive this migration. About Oracle Database (not Oracle company), I am very much in agreement that (PL)SQL can be use

Price is the only main reason I see which drive this migration. About Oracle Database (not Oracle company), I am very much in agreement that (PL)SQL can be used as one language to take care of Relational Algebra, Row oriented, Column oriented, Document oriented and also Blockchain oriented disk persistent tables with local node partitioning and distributed sharding, Graph traversals queries using recursive CTEs, auto tuning of indexes, streaming materialized views, distributed topic/queues. Oh by the way with little effort you can accomplish almost all what Oracle does with PostgreSQL and its community extensions.