The tsar was a king essentially
Have all kings been tyrants then?
Historically that term was reserved for especially unjust kings not monarchs in general
Autocratic rulers.....kings......tsars...etc who ruled for self at an excessive expense of his subjects
That is a tyrant...and Nicholas was not
I agree that Nicholas had no desire to be a tyrant, in fact he sincerely desired good for his people.
The problem is that he wasn’t competent enough to surf the waves of modernity crashing down on Russia. In the process he played a very large personal role in creating the situation that allowed the Reds to come to power.
One of the odder parallels in history is that between Louis XVI and Nicholas II. Both were kind, decent, honorable men who wanted the best for their people.
Both presided over the collapse of their monarchies, and got themselves and their families killed in the process. Neither of them deserved their fate, though lots of their ancestors certainly did.