For the company: infrastructure management. You don't have a local PC (other than mainly a low cost thing acting as a fairly dumb terminal) that may have parts fail and will otherwise need upgrades every now and then, with local work that may need to be encrypted and backed up, ... You are working in "the cloud", your environment is running on a common set of VMs/containers, a fault in a node just means a new one spins up (or you get shunted onto the still running ones), hardware redundancy is handled at that level reducing single points of failer, local machines don't need to be monitored for data/apps/other they should not have, resource management (does anyone run their dev PC at full tilt 24/7? no? so CPU/IO/other resources can be shared), ...

For the individual: similar concerns of hardware failures losing work go away a bit (there are still ways to lose everything, but less of them), easy moving between environments (desktop, laptop, phone), ...

Though it depends how much is pushed to the "cloud". You may still need some meat on the local resource bones if not pushing any CPU crunching into the sky too.

Essentially we are reinventing the thin client from the 90s/00s, which in turn reinvented many mainframe concepts, not that either ever completely went away, with an eye on much the same benefits.