Object Relational features in PostgreSQL

Hi everyone. I just finished a course on PostgreSQL and I found out that
PostgreSQL doesn't provide any object relational features (as claimed in
the official documentation), except table inheritance and very limited
user defined types (I defined a UDT with 2 attributes and couldn't use
it in a table, and the trainer said it must contain 1 attribute at most
so that it can be used (as a column) in tables)

So my question is whether there is (or will be) any support for (any of)
the following:

More flexible user defined types and support for these in tables

Type inheritance

REF and DEREF data types

Nested tables

Polymorphism and more flexible casting of objects (like the TREAT
function, not only the ONLY function)

Typed tables (create table X of type Y)

Object views

User defined functions (encapsulated in the body of a user defined type)

I would be really thankful for any fast reply, because I need to report
to the management whether a migration to PostgreSQL is both efficient
and possible or not.