Story Points let a PC start without any backstory - instead you get 5 Story Points, and spend them to:
know an obscure fact
know a language/ culture
introduce an ally to help with the current mission
et c.
By the time players spend them all, they should have a chonky backstory which was always relevant to the current mission, so no info-dumping required.
If all your points were spent introducing cousins and siblings, we have established the character has a big family.
If all your points were spent knowing languages, and knowing highly obscure knowledge, we have established the character as a very clever, and well-travelled person.
Good features
Speeds up game (no lore dump!).
Players are less pissed about their characters dying early on session 2 they haven't invested the work of writing an essay on their origin story.
It's probably the most popular part of the game whenever I receive feedback from someone reading (not playing) the game.
Bad features
Nobody spends Story Points
It doesn't replenish, so players hoard the points, refusing to spend them.
So far, I've tried:
granting 1 new Story Point over a long Downtime period.
granting XP in return for spending Story Points
adding a one-page rules summary to the table, including notes on what you can spend Story Points on.
demanding all new characters come from the pool of allies created through Story Points, meaning that:
it's better to have more allies, so new people have a wider pool of characters to select from, and
new PCs are never entirely new - they're known to the party.
...nothing works.
Everyone likes it in theory, nobody uses it in practice.
Brindlewood bay does something similar with 'crowns'. That system just requires each character spend at least one crown per session. If it doesn't come up naturally during gameplay, it has you do a short vignette right at the end.