Surprising behavior with pushing predicates down into a view

Hey guys,

Postgres version: PostgreSQL 18.2 on x86_64-pc-linux-musl, compiled by gcc
(Alpine 15.2.0) 15.2.0, 64-bit

I've been toying around with some financial data and I ran into a
surprising result with passing qualifiers down into views that may or may
not be intentional on postgres' part. I'm hoping you guys can help
clarify...

Here's the view. It attempts to calculate rolling 1 year daily beta across
all stock quotes in my table. The design intention here was to define the
"how" and leave it to the consumer of the view to define the "what" by
filtering down to the tickers and date ranges they care about:

https://gist.github.com/JustinChristensen/1cad256ea61ad30aa39d42aebc4557b9#file-view-sql

When I query this view using a simple constant ticker like 'AAPL' the query
plan shows that it correctly filters the set of tickers before applying the
return calculations, joining, and then calculating beta. I've included the
EXPLAIN output after the query in this gist.

https://gist.github.com/JustinChristensen/1cad256ea61ad30aa39d42aebc4557b9#file-literal-filter-sql

When I query this view using a subquery to find the tickers to filter on it
instead tries to execute the view and calculate the beta for all of the
tickers in the table before filtering:

https://gist.github.com/JustinChristensen/1cad256ea61ad30aa39d42aebc4557b9#file-subquery-filter-sql

I'm no expert... My expectation here was that it would be able to apply the
filtering first regardless of the form the ticker predicate in the outer
query takes.

Is this a bug? Working as intended? Something that could be improved but we
haven't gotten around to it yet? Sorry if this is a duplicate of something
you're already tracking.

Thanks,
Justin Christensen