I think it has to do with release dates of the devices and not if it's a premium or mid-range or entry-level device. The 7plus was probably chosen and approved by google for beta first as it was released before the Sirocco I guess. Just my opinion.
I think that it's been selling quite poorly and they can't motivate a super high prio, compared to the volume products... Still, it could be worse I guess.
Quite disappointed, with Android One and project Treble I was expecting very fast cookie upgrades. But now both Sony and OnePlus have pushed out Pie updates, and they have a ton of patches on top and are not Android One!
I don't want to sound like an antagonist in this thread, but now that I have my Sirocco I'm really impressed with the device. Currently setting it up.
Can't talk about all manufacturers, but the ones I had devices of didn't have a beta program or I couldn't partake in it to begin with and/or that I know of. So for me I'm impressed that Nokia has one.
Would be even more impressed if I can take part with the Sirocco.