I've been declining to install 2022.28.2 for over a month now because I don't want to get ahead of the next FSD Beta release's underlying base version. However, my car has already downloaded 2022.28.2. So eventually I will probably have to install it even if you are installing 2022.40.99 that day.
Other individuals almost certainly delay installing updates for a variety of reasons.
Some cars also only have intermittent access to WIFI, and thus may not download version X of software the same day Tesla authorizes them to download version X.
I believe that under
Controls > Software > Software Update Preferences you can still select either
Standard or
Advanced. In general I expect those who select Advanced will be installing higher numbered updates before those who select Standard.
From version 2021.32 of the North America Model Y user manual.
• Standard: Receive software updates using the normal rollout timeframe for your region and vehicle configuration. When a software release is made available it has generally been running on other customer vehicles for a period of time.
• Advanced: Receive the latest software updates for your region and vehicle configuration as soon as they are available. Tesla determines how, when, and where to send updates to vehicles based on various factors unique to each release. Keep in mind that although you receive updates as soon as they are available for your specific vehicle, you may not be in the first Tesla group of Tesla owners to receive the update. Choosing Advanced does not enroll your vehicle in Tesla's early access program.
As previously mentioned, it is unlikely that Tesla never wants to push out a new update to EVERY CAR all at once. They certainly want to test it on a few bleeding edge vehicles first, then a larger group, and so on. In part so they don't introduce a bug that affects EVERY CAR. Their nightmare scenario is a release which bricks cars, worst case requiring hardware replacement, almost as bad needing to be towed to a service center to have the software manually reinstalled.
Also remember that Tesla has a huge number of cars on the road these days. They want to spread the load on their servers and internet connection across multiple days, not have days or overloaded servers followed by days of idle servers.
As someone mentioned, dealing with the pandemic Tesla was very fast compared to other automakers at rewriting their software to run on different chips, when their preferred chips were unavailable. Though most customers never notice, their software release protocols certainly have to accommodate different hardware under the covers.
Lastly, I don't know about you, but my car certainly has not installed every point release. I don't know to what extent that is caused by my settings, my speed of installing once available, differences in hardware...