I’m currently reading the book “Game On!” About video game history, and had to verify.
When initially designing The Sims, Wright spent a great deal of time researching the fan community of the hugely successful Quake and Quake 2. “I was amazed at the time people were pouring into making their own custom levels,” he told Wired. “So with The Sims, we wanted to make it possible to modify everything. Players could use it as a storytelling platform.”
https://www.shortlist.com/news/15-things-you-probably-didnt-know-about-the-sims-4
Also I understand his house burnt down in the late 20th century, and the joy of rebuilding/furnishing was another motivation for the game.