Yes manual query preparation by client [1] is what you did in MSSQL server up until v7.0 I believe, which was 1998 when it started doing automatic caching based on statement text. I believe it also cached stored procedures before v7.0 which is one reason they were recommended for all application code access to the database back then.

MSSQL server also does parameter sniffing now days and can have multiple plans based on the parameters values it also has a hint to guide or disable sniffing because many times a generic plan is actually better, again something else PG doesn't have, HINTS [2].

PG being process based per connection instead of thread based makes it much more difficult to share plans between connections and it also has no plan serialization ability. Where MSSQL can save plans to xml and they can be loaded on other servers and "frozen" to use that plan if desired, they can also be loaded into plan inspection tools that way as well [3].

1. https://learn.microsoft.com/en-us/sql/relational-databases/n...

2. https://learn.microsoft.com/en-us/sql/t-sql/queries/hints-tr...

3. https://learn.microsoft.com/en-us/sql/t-sql/queries/hints-tr...