Interesting that this view of Luther was promoted in a Roman Catholic school - it wouldn’t’ve happened to have been an ethnically German area, would it? I ask because the view of Luther as “bold revolutionary” has its roots in the Prussian Union, not in Lutheranism (as others have noted, we could care less about the man - it is the Confessions, as a clear reflection of Scripture, that we follow).
A bit of history… To unify the various German states, the political powers of the time had to invent a single, common, national identity. Religion was a necessary aspect of German life to ‘nationalize’ and make a point of commonality. So Prussia
attempted to force protestant churches under one, single, unionistic umbrella partly through force (some Lutheran pastors were defrocked, jailed and even killed), and also through nationalistic rhetoric and propaganda. Luther, Calvin and Zwingli, were all relegated to simple contributors to some great German cause, rather than representatives of their separate reformations; this meant that Calvinists and Lutherans would have to celebrate their respective Reformations on a shared day. The powers that be selected the posting of the 95 Theses (October 31). Until that time, Lutherans mostly celebrated the presentation of the Augsburg Confession (June 25).
I’ve never understood the posting of the 95 Theses to be that big of a deal - they are actually quite Roman Catholic. Some Lutherans
still get rather ornery about celebrating them, and
Luther himself advocated their burning.