It looks like a political canonization to me. A controversial person, his martyrdom is highly questionable. A martyr is someone who was killed for refusal to renounce the faith, in the Stepinac’s case this is not a proven fact.
(1) One does not need to be canonized to be a saint.
(2) Not everyone who is canonized is a martyr - canonization does not equal martyrdom.
A question: why would this canonization be political? Clearly the forces of political correctness are marshaled against it, and there is little political advantage to canonizing a man the mainstream media are bent on demonizing.
Stepinac was an anti-Communist because he was a Christian believer and pastor. He was put on a show trial because he refused to join the Communists in subverting the Church. I suppose this was a political act from a Communist perspective, but from a Christian perspective it was the only thing to do.