Not a fan of Ryanair but let's not jump to conclusions. We might not know the full story yet.
Suffice to say, some airlines do carry medic kits. Depending on airline these can contain items such as a stethoscope right through to hard drugs to aid cardiac arrest and controlled substances for pain relief. Crew aren't trained to use these so it's absolutely right that passengers aren't able to either.
That said, basic items to treat injuries such as those consistent with turbulence should be available for cabin crew to use.
Like I say though, whilst I dislike Ryanair, I'm not passing judgement as I wasn't there. I also know how colourful passenger tales can be and you often hear passengers cooking up myths about why things are done this way or that way.
I just find it a bit far fetched to believe that even Ryanair crew would sit back and watch injured passengers suffer.