O'Leary is just trying to soften the troublesome competitor Wizz that has lower cost than Ryanair (Take the 2019 published total cost of each airline and divide it by amount of passengers)
Merging Wizz with the much higher cost than Ryanair easyJet will again make Ryanair the airline of size with the lowest cost base in Europe.
And that is why it would be bad for Wizz's profitability and shareholders. And possibly easy's watering out its premium LCC brand with Wizz's cheaper than chips brand. But easyJet might be doing a bit of the latter part themselves removing the easy part of their customer service by slowly copying Ryanair's most hated traits.