Do not scan index in right table if condition for left join evaluates to false using columns in left table

Hi, could you help to understand why Postgres scans index in right table in
the following case:

CREATE TABLE parent (
> id integer PRIMARY KEY,
> dtype text
> );

CREATE TABLE child (
> id integer PRIMARY KEY
> );

INSERT INTO parent (id, dtype) values (1, 'A');
> INSERT INTO child (id) values (1);

EXPLAIN ANALYZE
> SELECT *
> FROM parent p
> LEFT JOIN child c
> ON p.id = c.id
> AND p.dtype = 'B'
> WHERE p.id = 1;

Note that the only record in *parent *table has dtype == 'A', but the join
condition has p.dtype = 'B'.
The query plan still shows Index Only Scan on *child *table with loops=1.

Nested Loop Left Join (cost=0.31..16.36 rows=1 width=40) (actual
> time=0.104..0.107 rows=1 loops=1)
> Join Filter: (p.dtype = 'B'::text)
> Rows Removed by Join Filter: 1
> -> Index Scan using parent_pkey on parent p (cost=0.15..8.17 rows=1
> width=36) (actual time=0.018..0.019 rows=1 loops=1)
> Index Cond: (id = 1)
> -> Index Only Scan using child_pkey on child c (cost=0.15..8.17
> rows=1 width=4) (actual time=0.078..0.080 rows=1 loops=1)
> Index Cond: (id = 1)
> Heap Fetches: 1

In comparison, if using INNER JOIN, Index Only Scan on *child *table is
never executed.
Tested on PostgreSQL 17.2