2025? Why the delay? This should be out now! Maybe Apple's products are good because of the maturation process but I think in some instances, like this, they're shooting themselves in the foot. The iPhone this will replace is OLD tech.
The SE hasn't been about "old tech" it has been about lower bill-of-materials (BOM) tech. (yes, that often strongly correlates to 'old' but it isn't necessarily more affordable). Apple still wants their normal margins at the lower price point.
First, Apple is trying to maximally squeeze the costs out. for example.

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Second, (again related to costs) rumors are they are targeting the SE4 to be tightly coupled to the Apple cellular modem. So if the modem slides on deployment the SE4 slides on deployment. Pretty good chance the first modem won't be as good as Qualcomm's best modem ( so bleeding edge iPhone updates will continue to get that). Apple needs to put their modem into something that they can get out into the field in large numbers. An iPad placement would be more highly limited than the SE4. Plus, Apple can shift any Qualcomm '> $400 tax' over to offsetting the component costs increase ( bigger screen , FaceID infrastructure , etc. )

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The original SE started out at $399

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but by SE3 had slid up to $429

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Going to even more costly components could that price slide up to $469-499 . The major problem there is that it would get too close to the n-2 iPhone that is being sold in its third year also. SE1 -> SE2 was about 4 years. SE2 + 4 year would be 2024. However, if the cellular modem hiccups that could easily slide into 2025.
So until Apple can squeeze out their BOM target costs out of the phone ... it is probably not coming. The SE3 is a 'refresh' that is only 2 years old ( that is off the Intel modem issues. ). It is a viable 'buffer' to coast an extra year with some regular discounts thrown out to some low price retailers/service providers to keep the product moving at a "lower threshold" limit to keep them interested. .
Apple isn't going to cry many tears if folks in calendar year Q4 buy more iPhone 14's than SE3's. And if the SE4 is going to be a "more affordable" 14 , they are reducing fratricide now while the 14 is still in 'n-1' status.
P.S. The SE4 + Modem connection.

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[ Even if Apple decoupled them because modem was super-duper off track that would slide the whole thing backwards as a late replacement for a Qualcomm would still require another validation effort that would take time. Unlikely for a relatively low cost device that they were running parallel , highly overlapping development tracks for both modems.
I suspect that SE4 will also lack mmWave 5G like the SE3 . More so because Apple's modem just isn't going to cover it than saving RF component costs and licensing. ]
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