Looking forward to this! We've done a lot of work to tune our work_mem (and its modifiers) to the needs of our art community, but RAM is limited on our main server, and we do a lot of sorts for things like gallery listings with various filters, and I think we sort on a single column for recommendations (which have many exceptions, like "work the user already has as a favourite").
I'd previously noticed a significant performance improvement by converting defaults to nulls in some cases (the first eight are stored in a bitmask essentially "for free" in the first 24 bytes, so you can fit two integers and a null field into the first 32 bytes), but this didn't help many queries, so using less memory may improve them.
Thanks to all developers who worked on this and other performance improvements coming in PG 15! 😸