But they also have products with cc1310 so …
How many products with the cc1310 vs Lora? 
Node-side LoRa chips support standard modulations too, so if they could get a good deal on them, they could have placed them with the idea of continuing any existing FSK-ish plans based on parts from other vendors, but having LoRa as an option too. And one can imagine Semtech cutting them a deal to get widespread deployment of the chips in mains-powered infrastructure, hoping for even more sales for portable nodes to interact with it.
The really interesting question is what sort of network scheme it will turn out they built, when the “gateways” are constrained to receive on one frequency and set of modulation settings at a time, and how well that shares the band with theoretically more readily need-tuned LoRaWAN usage.
Are the Ring cameras going to beacon? Or do the dog trackers (etc) use a set of fixed calling channels?
Take a look at supported SFs (and take into account it also supports SF5 and SF6 mentioned in the datasheet but not mentioned on the page). This intentionally castrated and so cheaper version of SX126x seems to be a basement for Sidewalk devices. And SX1302, which also supports SF5/SF6, seems to be a core of Sidewalk GWs.
LoRaWAN for metering, hobbyists and a dozen nodes-size networks in rural areas; Sidewalk for consumer electronics.
Have you seen something that points to use of gateway-class radios in the system?
What I’ve heard about the silicon already being in devices in customers homes and just waiting for a firmware update makes me think they have a scheme to use cheap node-class radios in the infrastructure role.
In terms of range, I suspect it’s more a “managing expectations” - LoRaWAN can go quite far line of sight, yet, but obstructions may mean less in many situations, especially when the infrastructure consists mostly of IP/LoRa bridge devices that may not be very well placed from an antenna siting perspective.
Though this is just a rumor 
What does Semtech “CoreCell” have to do with “Amazon Sidewalk”?
Of course Semtech wants to sell expensive gateway silicon, even a cheaper version thereof.
That doesn’t mean that Amazon is buying it for their system.
That’s not to say that they might not go down that route ultimately, but it didn’t seem to be what the sidewalk scheme was initially about.
we’ll see soon.
The fact that my post was edited by someone else says a lot
Not really - such edits are transparent and as you can see was done recently and by Wienke himself - looks to have just removed “CoreCell” reference/graphic (reasons unknown - copyright/use? meant to copy for own use but clipped/cut out instead?..)). “-\Shrugs Shoulders/-”
As can be seen from these links CoreCell is spcifically called out as a cost/power reduced implementation and ref design for indoorgateway ref design and building monitoring systems (vs Sidewalk implying external?!) <shrugs shoulders again! > As referenced above some products have made use of LoRa capable node silicon offerings, but potentially using legacy modulations vs LoRa?, no declaration of use of GW si yet…could the 1302 be a logical extension and use case?!
That’s a long stupid story 
himself?
or atleast someone with his account user/access on forum
Enough speculation wrt Sidewalk until we know more officially in the longer term me thinks! So will close thread.
Update Jan 28 20:
Ok after 1 more post for now! 
Post in Library 12…
The LIBRARY basement part 12 https://www.thethingsnetwork.org/forum/t/the-library-basement-part-12/31682/64
More PR around Amazon Sidewalk
Note reference to ‘crowd sourced’ network
No specific call out of LoRaWAN - only mentions LoRa directly in the release
Amazons Blog post on the story:
Note reference to “will support multiple protocols including Bluetooth Low Energy (BLE), Frequency Shift Keying (FSK) and LoRa in the 900 MHz band”.
The LoRa exclusiveness is now lost.
I dont recall that it was ever LoRa only but rather it was emerging as a multiradio solution - dont recall wifi though I know Borroz suggested it might involve a LoRa - WiFi Mesh system and I beleive one of the devices called out earlier in the thread may have had capability as a WiFi-LoRa/FSK bridging device. I think some of the early ‘Ring’ brand product that were commented as potentially part of the early system development were multi radio per the FCC submissions.I believe idea was devices would opt for the ‘best fit’ available locally or depending on distance/proximity.
Update
More info coming out e.g. here: