DivestOS is my favorite Android OS. I’m using it on my old harpia since about ~7 months.
It is imo the most secure and privacy-friendly OS for many old Android devices, making it the best choice for those who either cannot afford a newer Pixel or just want to use their devices as long as possible, e.g. for environmental reasons.
I can also recommend the other Divested projects, e.g. Mull.
IMO the biggest problem for DivestOS is the lack of publicity - if more people knew about it, they could benefit from it and more donations would come in.
So I would love to see a Techlore video about it! 
