Foolish men contend with God in many ways, as though they held him liable to their accusations. They first ask, therefore, by what right the Lord becomes angry at his creatures who have not provoked him by any previous offense; for to devote to destruction whomever he pleases is more like the caprice of a tyrant than the lawful sentence of a judge. It therefore seems to them that men have reason to expostulate with God if they are predestined to eternal death solely by his decision, apart from their own merit. — Calvin
God is God, for Calvin, and free to decide whatever he wants to decide and if you don’t like it, well, too bad. The universalists hate that so much that for them God elects everyone to salvation (in spite of the complete absence of any such notion in Scripture) and the angry atheists hate that so much that they attack a God which they don’t believe in (which is, by all accounts, more an indication of madness or mental illness than anything else).
God is God and he can indeed do whatever he wants. And, truthfully, if you think God should do what you want instead of what he wants you really are quite unhinged.