The amount of confusion being put out about the next generation of Xbox devices isn't too dissimilar from the ocean of rumors that surrounded post-Saturn SEGA before the Dreamcast was officially announced. Back then, multiple partners and specifications were mentioned, from Lockheed Martin to 3DO (M2), etc. and then even with Dreamcast there was Blackbelt, Dural & Katana being simultaneously worked on before one was finally chosen. All reported by magazines & the trades of the day.
I think some of this confusion with Xbox hardware going forward, is intentional on Microsoft's part. They want to distract people from the absolute failure of Series X & S when it comes to hardware sales, they want to mitigate some of the perception damage they feel their multiplat strategy for non-Xbox consoles will do with hardcore fans, and they probably restarted next-gen development from scratch over the past year after it became clear Series S & X weren't working.
This is all preliminary, but I'm starting to piece together what the next line of devices could actually be. In short, I disagree with you on that it'll be another traditional console: that model just doesn't work for Xbox anymore, especially now that they're going more fully multiplatform 3P. But you're right, in that the new devices likely won't be outright PCs, either. Here's what I think is really going on:
-Replacing Xbox OS with a custom implementation of Win32 & Windows kernel
-Integrating Xbox OS & XDK libraries into said custom Win32 OS (over time, and also into general Windows)
-Likely retain Xbox OS for legacy purposes only, ran through hypervisor layer as an Other OS (dual-boot) choice (for all the various App X Xbox games & Xbox Store)
-All NEW games will only support the Win32 & associated kernel implementation, but effectively be PC builds customized to fit with the system spec
-MS Store & Game Pass integrated in new frontend UI for Win32-based OS (based heavily on Xbox OS UI for Series consoles)
-Alternative storefronts (i.e Steam) accessible on Win32-based OS, but either outright (pay higher cost for hardware upfront) or behind a Game Pass subscription (soft-subsidization)*
-IF Microsoft manufacture systems, they'll probably only do soft-subsidized options while OEMs do zero-subsidized ones
-Some support for specific whitelisted Windows apps from the Microsoft Store, can run under the Win32-based OS
-MS licenses out both OSes (Xbox OS, Win32-based OS) & associated UIs to OEMs for their partner devices; allows UI/frontend customizations (within spec)
-MS works with partners (i.e AMD?) for a performance specification/architecture, entailing R&D costs, but leaves device manufacturing to licensed OEMs. MS may design a reference device for OEMs to base things around
-Two different spec platforms: one for non-mobile/handheld, one for mobile/handheld, sharing tech. Both with some degree of scalability (boost/lower clock rates, enable/disable shader cores etc.)
-Some range of modularity for non-mobile/handheld spec including types of supported GPU upgrades (i.e low profile, within certain range of performance etc.), I/O ports (Thunderbolt, USB-C, Ethernet etc.), system RAM support (e.g 8 GB, 16 GB, 24 GB etc.), all depending on what the chipset supports
-Some range of modularity for mobile/handheld spec including output resolution support, touchscreen support, types of custom button config support etc.
-Strong likelihood of NOT being called an Xbox (maybe still retains an "X" letter somewhere in the name)
-Initiative slowly phased out over the gen as features specific to customized Win32-based OS implemented into general Windows & kernel, and missing Xbox OS & XDK libraries implemented into general Windows & kernel as well.
That's about the gist of what I'm expecting at this point. That, assuming the "Xbox" handhelds coming later this year underperform, and I expect they will considering all the things they'll be missing. As for price, I think it heavily depends on if MS actually manufacture any systems themselves. If so, I think they'll only do soft-subsidized version while still keeping the base price at least 25% higher than comparative SIE & Nintendo systems just to ensure better margins for OEMs.
For example, if the PS6 MSRPs for $499 (cheapest option), then the 'Xbox' equivalent soft-subsidized by MS would
probably retail for $629 - $649. They'd have to find some way to justify the higher price without relying on access to Steam, since you'd still need to pay more to access it on a soft-subsidized device. Maybe offer six months of GPU for free or just rely on the selling point of the features.
But supposing the person already has Game Pass (e.g GPU), maybe the amount they pay to get access to other storefronts lowers depending on how long they're planned to subscribe for and the tier. So back to GPU example, maybe that access is just an extra $5 a month for the length of time of their GP subscription. If the person doesn't have Game Pass at all though, they'd have to subscribe to the highest tier for a fixed time that includes access to alternative storefronts. Or, they subscribe to whatever tier they want to begin with, then if they decide they want access to Steam etc. they pay a determined additional rate for the remaining duration of their subscription.
Meanwhile for OEM variants, I imagine if they had a PS6 equivalent they'd price their option around + 50% that MSRP, or $749. But these would be non-subsidized, so you can access Steam and other storefronts upfront. Since OEMs aren't doing the R&D for the CPU, GPU etc. there aren't costs on that front for them to make up, plus the padding MS would put on their own equivalent device MSRP would further benefit OEMs, who would collectively increase the volume of supply.
However, a $749 MSRP is also assuming it's rather bog-standard to the MS equivalent in practically every feature. If OEMs were to, say, strip them out with a crap ton of Thunderbolt 6 ports or a higher-clocked version of the CPU, or much larger & faster internal storage, they could charge more.