Manjaro is frankly the least stable Linux distribution I've used to date. I
have never had that many issues over time with a minimal Linux installation 
that gets upgraded every once in a while. It seems like with every new upgrade 
of its packages, Manjaro decides to change something that will end up in my 
devices not booting anymore or not having network connectivity anymore. And 
this is as true for the RK3399 SBC as it is for the Pinephone Pro.