I'm not entirely sure how much I'd trust a SA-X longer term.
Gearbox wise in Auto terms Mazdas was designed by papyrus by a man who wrote in pictures. It's very much a torque converter from old-school with most of the advantages and disadvantages that brings.
A friend of mine has a CX-5 163 auto and it manages 38mpg which can't decide is impressive or not. For a 2.0 petrol auto SUV that is good...for a modern car that's pretty awful.
But it's a case of whether or not going SA-X and gaining maybe 5mpg would just end up with a bunch of other bills in the future for stuff the basic 2.0 doesn't have.
Having recently spent some time and money dealing with "modern car problems" (inlet coking) I can safely say that saving a few MPG doesn't necessarily balance the books over time if it comes at the expense of additional complexity.
Thankfully in my case I managed to beat Citroën UK into submission and they picked up 70% of the bill but Mazda has a terrible rep for goodwill out of warranty and the superchargers etc seemed problematic early doors.
For those reasons, I never buy cars with brand new engine tech - I would wait at least 3-4 years until it was reasonably proven. The Skayactiv-X tech has been around since 2019, so it would be 'on the cusp' if I were currently in the market for a new car. As yet, I have not come across the level of problems associated with the SA-X tech as with Mazda diesels, in fact nowhere near as much. More problmes (seemingly common with almost all modern cars) from electronics because of all the complex systems and tech cars now seemingly come with.
I fully appreciate the lack of enthusiasm about Mazda UK / many dealerships and warranty claims, given past experience.
The above is precisely why I'd avoid diesels or high trim level models with all those so-called 'safety' gadgets and other bits I don't need.
I'm far less concerned about their use of 'traditional' TC autos, as they are both a proven design for reliability, smoothness / ease of use and have improved quite a bit in terms of mpg. The CX-5 is quite a big brick of a car and thus 38mpg (presumably average) from an auto version is quite decent, especially when compared to the cost of fixing a DCT 'auto' and their much lower reliability over the medium to longer term. To date, I've not heard of any problems with Mazda auto boxes, unlike with Ford (with dropped theirs and went back to TCs), VAG and Renault/Nissan DCTs.
Yes, the current high fuel prices will tilt the balance towards DCTs, but nowhere near enough to matter, at least to me. But then my 'aged' Mazda3 1.6 petrol is supposed to do an average of around 38mpg (I get 40.5mpg), so 38mpg for a more powerful, quicker, larger/heavier car in auto form is quite good.
One application of the 'newer' tech combining with established, reliable designs is that used by Toyotas where the use both port and direct injection to avoid problems associated with inlet valves getting gunked up.
Mazdas with the SA-G tech (the SA-G does as well) seem to fair better than some other makes on this front even though they only now use direct injection, but I suspect the level of the problem is related to the driving pattern (repeated short trips from cold far worse than mostly longer trips).