T's usually don't openly discuss attachment styles but thankfully my main T has so I have a clue why he does what he does.
I think that T's assume that "secure attachment" is the ideal to be obtained, but this may not be true for everyone.
I think I am anxious/preoccupied which explains the need for praise, needing reassurance that T won't leave abruptly, the desire for acceptance and affection.
I am a bit admiring of dismissive types because they are so self-contained and self-reliant. I can be a needy mess but I'm getting better