Part of the reason is that Intel drops their own support for chips.
Hi everyone, We would like to remind all customers that Intel will no longer be providing functional and security updates (Servicing) after September 2022 for the following products code named Skylake: 6th Generation Intel® Core™ i3, i5, i7, and m Processors (CPUID: 406E3) Intel® Celeron®...
community.intel.com
They stopped supporting skyLake in September 2022, so Apple pretty much had no choice but to drop support for SkyLake and earlier with the October 2022 release of Ventura. If Intel literally wouldn’t give any support for new drivers, security updates, etc. for those earlier chips, Apple reasonably couldn’t promise that same support either. It’s the same reason the Windows 11 system requirements were also so strict when it was released.
Obviously, people are going to conspiracy theory, wine, and complain that it’s Apple “ planned obsolescence, Tim Cook bad, Steve would never, etc etc etc” but I seriously don’t think that is the case. The fact that the iPad Air2 from 2014 and the iPhone 6S from 2015 just received another security update… Yesterday, 10 and 11 years after initial launch, kind of tells a completely different story.
Also, the fact that there have been plenty of models over the years to get tons and tons of extended support, the mid 2007 iMac received the latest operating system until 2016, and security updates until 2018, 11 years after the thing launched.
2012 MacBooks were receiving security updates until last year.
So in short it’s three reasons.
A: third-party drivers and security compatibility from Intel and apples older graphics partners.
B: day to day stability and decent enough feature parody between models.
C: the natural marching on of time.