I think it detracts from the legitimate case Ryanair crew may have regarding their conditions of employment to try to leverage the point by questioning safety.
The rules and regs are clear, if someone has been fired for taking extra fuel I would be interested to see those facts, otherwise it's for the PIC to decide and also right for him to offer an explanation to his employer as to why he feels it necessary to deviate from the planned fuel.
Everyone knows Ryanair's business model when they join and yet they complain when they have to abide by it....vote with your feet because I struggle to believe Ryanair brake any rules, it's just too much of a gamble for them to do so, however, I don't dispute they probably operate with zero fat over and above the rules and if that makes one nervous, then lobby to change the rules, but don't claim they are unsafe.
This case to me is like the "aggressive tax avoidance", don't blame companies for doing what is economically advantageous for them within the law, if you don't like what they do, change the laws.