The key to success here seems to be a standardized OSS app store. Somehow.
On the other hand, I feel like the Raspberry is no longer a good platform to build on. It is impossible to buy, and when you can, it is going for many times over any reasonable price.
Broadcom's proprietary offerings have got a lot of people into SBC's, but now there's a market AliExpress is full of Banana, Mango, Lichee and Radxa boards (to name a few) which outperform the Raspberry family in pretty much every way.
Even the communities are growing, which has always been Raspberry Pi's strength.
On the other hand, I feel like the Raspberry is no longer a good platform to build on. It is impossible to buy, and when you can, it is going for many times over any reasonable price.