I don't doubt that he made a sacrifice to be a hero. I would questions his motives though.

[Even Dead I'm The Hero? That's an arrogance that Beck can relate to - and actually also accomplished, through that stinger against Peter. Being proclaimed the 'greatest superhero of all time' was a win, even if he had to die in the process. With that mindset, he also doubts Tony's own sincerity. But that's where they differ. Beck's morality is skewed way further off than Tony's and he hasn't yet learned his lesson in compassion or truly caring about others besides himself.]