The reason for the timing is likely that The Sims was released on february 4th in 2000 so it is the 20 years anniversary.
The Sims is where I learned the appropriate way to interact with others based on what provided higher relationship status. I grew up in a very rigid, structured family without a lot of external interaction so this was my primer to "succeeding" later in life. I still experience crippling anxiety from social interactions, but at least the The Sims provided an appropriate socialization path to allow for quasi normal relationships with coworkers.
I played quite a few of the Maxis games and I thought that the Simlish of the Sims was the natural progression from the Sim noises of SimCopter which can be heard here:
Sim Copter was indeed the first appearance of the Sims. The Sim character tree editor was first used for Sim Copter, which was in development concurrently with Sims. They were "project X" and "project Y" respectively.
SimCopter must have the been first RPG I put a lot of time into. Kinda messed up and buggy but I had a lot of fun, I think.
Heh, based on the title I first thought it was a novel domain specific programming language, not a human language!