If you're not travelling HBO on a route with many flights the BA flexibility to switch flights beats the standard Ryanair fare.
Ryanair's sales pitch is relentless throughout the flight.
The differential between HBO and standard flex fare with baggage is usually much bigger on Ryanair than it is on BA.
That said, the Ryanair flex fare allows for a free flight change if you turn up in the hour after a flight.
If I had BA silver status or better and fares were pretty close I'd be on BA and ensure I'm fed and watered in the lounge ore-flight.