“better prepared for a job if they have Office skills”
Anyone who might be scared to use LibreOffice, etc, because they will be “better prepared for a job if they have Office skills” is making a false argument. Microsoft Office isn’t that different to LibreOffice, it mostly just (nowadays) has a weird menu/toolbar/“ribbon” structure.
Anyone who is so hardcoded to using just one application by rote is going to be completely fscked the next time Microsith decide to mess with the interface. Using LibreOffice at home will if anything only enhance your skills because you will be more used to and more resilient to changes in working practices.