The central case I'll focus on is that of digital people just like us, perhaps created via mind uploading (simulating human brains). However, one could also imagine entities unlike us in many ways, but still properly thought of as "descendants" of humanity; those would be digital people as well.
In particular, Karnofsky argues that digital people would have the same moral standing as humans (cf. moral patient), would accelerate economic growth and scientific progress, and could cause a "lock-in" of values. Karnofsky writes:
Most of this piece would apply to roughly any digital entities that (a) had moral value and human rights, like non-digital people; (b) could interact with their environments with equal (or greater) skill and ingenuity to today's people. With enough understanding of how (a) and (b) work, it could be possible to design digital people without imitating human brains.
Hanson, Robin (2016) The Age of Em: Work, Love, and Life When Robots Rule the Earth, Oxford: Oxford University Press.
Karnofsky, Holden (2021) Digital people FAQ, Cold Takes, July 27.