It’s like the focus is on the MacBook Pro as being the greatest profit centre, and the iMac, MacBook Air, Mac Mini and Mac Studio are kind of left to be updated in bits and pieces
I think that’s unfair to the people who work brutally hard to deliver the products we love at the blistering pace they do.
The MacPro didn't even make the enumerated list above. every 4-6 years is a blistering pace? Not!
The pacing here is in part set on cost recovery of the M-series chips being utilized. To 12 month 'churn' the MBP 14/16" models on Max's means the Studio with Max's goes slower because there is no "hand me down" product for the SoC package ( which pragmatically needs to be sold for more than just 12 months. Intel , AMD , Nvidia ... general chip makers do
NOT make chips for only 12 months. The hype train may more onto the next cycle in a year, but the previous processor products are still made and sold.).
The iMac is getting similar 'treatment' the Mini got in last 8-9 years of Intel era.
There are just so many moving pieces in development, manufacturing and supply chain that even Apple is unable to update all computers to new chips all at once.
The Mac Pro not being upgraded to a M3 Ultra is blocked with what high hurdle from the list above. The SoC itself is in the Studio; so it exists. Development. The ports on the MacPro are different how on a Studio ( other than more of them)? Huge development task? Nope. Supply Chain... massive numbers of Mac Pro's being sold now (or with a M3 Ultra )? Nope. Same case, Same power supply, same fans, same 8-pin aux power connector, etc. etc. Huge logistical hurdles? Nope.
The Mac Pro is a 'copious spare time product'. Was back latter half of Intel era and still there now.
The churn on the lower part of the Mac product line up is supported by they have other places to stuff plain M-series to. iPad Pro and then "hand them down" to iPad Air as 'new' . Throwing a chip the size and development complexity of the Max into the trash can every 12 months extremely likely doesn't make any economic sense at all. So it doesn't happen.
[ cost recovery for development is not 'development' itself. Making profits is a factor here at least as high as those other 3 mentioned. ]
In PC space they are getting a bit constipated with multiple generations with not enough places to go.
"... Chen said that multiple generations of x86 chips from both Intel and AMD are already proving to be complicated— the entry of Nvidia as a third potential supplier will likely make procurement and inventory management much more challenging. ...
Nvidia’s entry into the CPU-making business through Intel will definitely give tech enthusiasts more options — but it will also make it harder for manufacturers to find the right pairing of CPU, GPU, RAM, PSU, etc., that buyers will appreciate. And for the common person, this could just lead to decision fatigue, where they will just settle for the brand they’re familiar with. ..."
Acer leadership has some thoughts on future chip supply chain developments.
www.tomshardware.com
There is a substantial among of dogma that got built up around the general PC industry when it was in serious double digit , year-over-year growth phase. Part of the that is this 12 month cycle thing.