They can't be serious... Everything and absolutely everything these days is happening online, through various sharepoint, workday, etc. apps. Covid19 is only accelerated this. Simply thinking that someone won't take a screenshot and share it with some friends in the industry on various chat apps or email is naive. They can threaten as much as they want but this will never change. The genie is out of bottle since they elected to embrace such platforms for cost saving, mind you.
On the deadhead subject i find it ridiculous that while passengers are subject to various restrictions upon travel and crew who are sitting right next to or in between them, or worse standing in the line for security and boarding are expected to operate the next day (or the same - just have a look how they handle deadhead duty...) with being exempt from such restrictions. Cost saving again by evading rules and regs to ensure minimum crew is sufficient being shuffled around between various bases with no respect to individual health and safety concerns.