a lot of work remains to be done. we need to better understand the ways these systems fail. total closed loop, i don't think so. with periodic supply runs, probably say 95 or 99% closed loop. lunar regolith could be processed to produce some resources, same with martian terrain. you would still want most of your technology (and it's very long supply chains) shipped from earth, and whatever other resources you happened to need.

quality of life is a concern. modern electronics would take a very substantial population, probably in the millions to produce in situ and that's assuming they build off already researched technology from earth.