I believe the website is built on a LAMP stack. It is possible to create a section for "inactive members".

However in real life it's never that straightforward. Doing that will likely break something else, which will then need fixing... Usually an important function. Because it will edit the users then the server would (from memory) require a reboot.. It's not the same as your home computers. Some Servers can take days to get up and running after a soft reboot.