When you critique Tintin you're not relentlessly criticizing a French comic, you're relentlessly criticizing a Belgian comic. :D
Some of Herge's output was racist, but since at the time such things were common, whilst reprehensible in hindsight he was hardly the sole, or by any means the worst, offender. Plus with the likes of "Tintin in Tibet" I'd say he made a definite attempt to rectify things. Sexism hardly features since very few female characters feature, and Bianca Castiafiore is more of a caricature than anything else.
And I really can't hold a borderline broad farce like Asterix tends to be particularly guilty of racism or xenophobia, since they make as many jokes about the French as they do about anyone else. It's a comedy of stereotypes without much claim to reality and that's half the charm.
Plus whilst you may not enjoy the BD you've picked up, the joy is that there are always plenty more to pick from, in a wide variety of themes and styles.