While people are calling the new version a reboot, it feels more like an evolution. WP8.1 to W10M was a reboot, specially because the UI was drastically different. CShell feels more like Windows 10 Mobile was heading there anyways (with the whole one Windows motto). For consumer facing purposes they need to do some serious marketing if and when they launch, explain the OS, UI and benefits to people (kind of like how Nokia used to market when they first went Windows). Where I live, most people have a misconception about Windows Mobile, that it is difficult to use. If I give my phone to an android/apple user they start scratching their heads - for them (and most people) accepting something new or different from convention is very difficult, because everyone around them has an android or apple phone which they can relate to.
There is a lot of education to be done in their marketing, and not just for mobile, but PCs too.
Personally, it used to annoy me that someone who uses a smart phone, who understands the basics of a smart phone (there is a home screen, there are apps, there is an app list, settings, phone, SMS) is unable to "understand" Windows Mobile, like it's not as if Microsoft made an OS that is a radical departure from other OS, but now I've come to accept that people just don't care enough to try and figure things out.
They wants things fed to them, and Microsoft needs to go out there and explain it to them in their marketing efforts.
Reminds me of pre-smart phone days when everyone around me was using Nokia phones and they had a really hard time using my Moto Razr v3i - Nokia's action button used to be on the left, Motorola had it on the right, and the call/decline buttons were reversed too. A person once literally asked me how to make a call on my Razr, which he could not tell by the colour of the buttons for some reason, and I when got a bit annoyed he said he had to confirm because the action buttons were opposite.
So yeah, it's not just about apps, it's not just about a reboot - people need to be taught about Windows 10 PC, Windows Store and then transition into mobile, with things like 'Buy an app once and use on all your devices (UWP)'.