There have been attempts to make the Pi boot faster (by disabling the initialization of various subsystems), e.g.:

https://github.com/IronOxidizer/instant-pi

https://himeshp.blogspot.com/2018/08/fast-boot-with-raspberr...

https://kittenlabs.de/blog/2024/09/01/extreme-pi-boot-optimi... (previously featured here too https://news.ycombinator.com/item?id=41420597)