Yes, if you are exclusively pedantic, then it is not an exact fit in the meaning. I would argue that the common use of the word reactionary = person who reacts

Yes, if you are exclusively pedantic, then it is not an exact fit in the meaning. I would argue that the common use of the word reactionary = person who reacts to something inappropriately. But getting lost in pedantry instead of just moving through common usage when in regular human discourse is useless. There is no reason to walk down that road, other than to obfuscate any point the other person is trying to make behind a smoke screen of pseudo-intellectualism. Sort of like I tried to do with those last two sentences.