Pre-made families are the heart of the lore of The Sims and tracking their progress through the various games is one of the best ways to keep up with the timeline of the series. The timeline was thrown out the window with The Sims 4, which takes place in an alternate dimension rather than in the usual timeline, and so many of the usual fan favorite families players are accustomed to showed up looking very different in The Sims 4, prompting a call for fundamental changes in The Sims 5.
Not all of these changes were popular with players, with some yearning for the families that were, while other Sims families have had the opposite problem in having no interesting updates at all and are now in serious need of a reboot to remain interesting. These are the families that need a some retcons going forward; not so much that they're unrecognizable to players, but so that they're restored to their original selves, or given features that make them compelling.
The Sims 5 Needs to Return to Its Roots
The Caliente family took the spotlight in The Sims 2 when they became key suspects in the disappearance of Bella Goth. Bella Goth was one of the most popular townies in The Sims, and much of The Sims 2's lore was structured around her sudden disappearance, which spanned across different worlds and even included aliens. The Caliente family, then, was a disappointment to many fans in new The Sims 4 timeline, where they have very little to no connection to Bella at all, have a new mother who never existed before, and don't have any sort of relationship with Don Lothario beyond him living in the same household.
This is a simple case of The Sims 4's lore not aligning with its gameplay, which is a common problem across the game. The descriptions for Sim households and individuals explain relationships and rivalries, but actual in-game relationships are neutral or don't exist at all. The Caliente family is a victim of this system, and needs an entire reboot in order to return them to the devious family from The Sims 2 that the fans loved. Katrina needs to be removed from the picture entirely as she was never a member of the family in the original timeline, and replaced Nighat Caliente as the mother of Dina and Nina.
Lore in The Sims Needs to Matter Again
Another family that needs a retcon is the Pancakes family; intended to be the new "default" tutorial family to guide new players, the Pancakes family made their debut in The Sims 4 and thus didn't offend fans for being too different from their former counterparts. The biggest problem with the Pancakes is that they replaced the long-time fan favorite Newbie family, who were the original tutorial family dating back to the original The Sims. Players had seen the Newbies as a married couple, their descendants, and the pair as teenagers, and had a connection to the family; there was no reason to replace them, especially as they became available later on the official Gallery.
The Pancakes can remain in The Sims 5, but they need to exist alongside the Newbies rather than replacing them altogether. This Sims family needs to become more interesting as well, where the implied lore of the conflict between Eliza and Bob is actually implemented through gameplay rather than being ignored. Bob, as "the least interesting Sim in the world", needs to live up to the title the Sims team has given him, and his starting relationship with his wife needs to be bad as opposed to above average if they're supposed to be in an unhappy marriage, as their bio states.
The Sims 5 is in development.