consonant and dissonant mean different things in different contexts.
The thing is that even that an equal-tempered A2 is the same as an equal-tempered m3, our ears interpret them as different intervals depending on the tonal context.
Not to mention the notion of "consonant" and "dissonant" have multiple meanings depending on the harmonic and theoretical contexts. For instance, a P4 is considered dissonant by many in certain contexts.
The bigger picture is that gross generalizations are not very useful in regards to intervals like this: an A2 sounds like an A2, a M6 sounds like a M6, etc. A generalization of sorting all the intervals into two boxes "consonant" and "dissonant" is not helping you musically (in my opinion).