Duke, from the abdication in Holland, there are multiple items of opinion, especially in digital media conservative going in that direction. And when news have emerged concerning the scandals, some have responded with direct attacks to princess Letizia.
That does not mean that the king or the royal family, are behind this strategy, mainly because for them it would be a suicidal strategy ... but it is evident that there are certain sectors, they think that's a good strategy, and that is their way to exert their power and influence. That princess Letizia profile ... commoner, intelligent woman, professional and progressive ... is the opposite of what they would wish (puppet, submissive and easily manipulated), also helps.
Note that in Spain there is still ultra conservative groups, not very wide, but very strong. They had absolute power with Franco, with the King they lost much of that power, and with the next step they will lose even more. For these sectors Letizia has been a fairly easy victim to question.
For some, protecting the Crown, is to protect members of royal blood, and those they can get to forgive all ... but members who do not have royal blood, are pawns in a game, in which when interested, you can remove them. ABC news of attacking the princess, reflects that thought... and many attitudes of the King, too. It is ridiculous to see how the king is willing to do anything to protect and save his daughter, but does not move a finger to defend his daughter in law and future queen.
Past mistakes have led to the present situation. At this time in Spain, most of the sectors of power are so mired in corruption that anything that serves to divert attention, is welcome. And Princess Letizia is very useful for that.
I do not think a newspaper as ABC, which has been linked to the monarchy for decades, which has never fallen to the Crown sensationalism ... and in which the princess herself worked ... has decided to change radically. I think what is behind is something more powerful and important.