Agreed. Staff travel has been "removed" or "embargoed" in the past during industrial disputes for all staff. Usually restored. Your entitlement (not right) to staff travel is also suspended when off work sick.
It is not unusual to remove staff travel entitlement. The difference in this case is not restoring the entitlement. BUT they were warned.
We seem to be at cross purposes here. An embargo is not the same as removal of entitlement (and by 'right' I meant entitlement, if you want to split hairs). An embargo is by it's very nature temporary. Staff affected by an embargo know that it is temporary and just due to circumstances, and that everything will return to normal for them in due course.
An embargo on staff travel for all staff during a strike to avoid having staff stranded all over the place is very different to having your entitlement to staff travel removed. Staff affected by an embargo still have an entitlement, and can go on applying for tickets for periods outside the embargo period. My spouse has had his entitlement removed during IA 3 times in the early part of his career, and restored as part of the settlement, but has been affected by an embargo more times than I can remember.
As for no entitlement during sick leave, that is a pretty obvious restriction, to avoid people self certifying sickness just to enhance holiday allowances.