It may be somewhat subjective, and it is probably hard to compare the many airlines that have had no fatalities or serious accidents (reported at least) in the last 30-40 years; like Ryanair has.
But you said Ryanair were the safest of any airline (by far), which seems strange as there are many airlines with similar safety records as Ryanair. Why should they rank above everyone else?
In the end the customers will decide, but hopefully we can avoid another load of customers hitting the ground in MAX (or 8) crash.
I'm not sure about serious accidents, but there seems to be many airlines with no fatalities in the past 40 years. But perhaps Qantas just stays #1 since it has had no jet-plane crash (and no crash at all since 1951). Or perhaps it's the "Rain man" quote where Dustin Hoffman says Qantas never crashes; that cemented their position as the safest airline in history.
Ryanair certainly seems very safe, but with all those new MAX planes, who knows how long that will last.
https://www.cnbc.com/2021/01/06/what-are-the-safest-airlines...
It seems Ryanair does not make it to the top 20 in terms of being the safest airline. Ryanair comes in at the 7th place for the low-cost-airline safety.
It could mean that Boeing are handing out huge discounts, or that Ryanair bets on these planes never making it to market, forcing Boeing to give them a killer deal on a replacement plane etc.
The thing is that most passengers that have read any of the articles about this plane, will never set foot on one of them.