It's not just Tin-Tin.
People have complained about racism and sexism in Babar the Elephant:
http://www.nybooks.com/articles/17640
And about the racial stereotyping of the oompah loompahs in Roald Dahl, not to mention the gender stereotypes in Enid Blyton.
My feeling is that if you start to allow censorship then it is difficult to see where to draw the line. A lot of good stories would be banned or censored.
However, perhaps parents could use these books as an opportunity to discuss racism and stereotyping with their children. My daughter loved Enid Blyton. But someone had made marginal comments in our local library books ("Why does Anne always do the washing up?") and this got her thinking.