Yes he was right. He never went against the bible. He was just fixing the human interpretations of the bible. Got never said a priest can't marry, and luther stood up for that. The Roman Catholic Church was in the wrong doing for selling indulgences. People could barely afford to feed themselves and the church was forcing them to pay taxes to build expensive projects in rome
Many of his theses were justified and uncontroversial amongst Catholics. The problem was that some fell into heresy and all were used to justify it. Separating those foolish enough to believe him or ambitious enough to use him from the Bride of Christ is a terrible thing which lead to war and the damnation of souls, not reform.
As Hillaire Belloc put it:
Heretics all wherever you be /
In Tarbes or Mines or over the sea /
You never shall have good words from me /
Caritas non conturbat me
Martin Luther single-handedly began the reformation of the lumbering behemoth that was the Catholic Church. The selling of indulgences, repressing of scientists and intellectuals, and violent repercussions for critics all promised to hold Europe back from development and morality.
The wars resulting from the reformation were more or less inevitable; people grew tired of the Church's constant abuses, and Luther's attempt at peaceful reform rather than resorting to violence to throw off the oppressors was both noble and somewhat successful.