How do you know when the change will affect the matview? I don't know the syntax for creating it off the top of my head, but imagine a materialized view limited to the top ten records of a table.
Hopefully, some of those restrictions will disappear, because matviews are often used to store pre-aggregted data, so the restriction on GROUP BY would be unfortunate.
Hopefully, some of those restrictions will disappear, because matviews are often used to store pre-aggregted data, so the restriction on GROUP BY would be unfortunate.