i think you conflate issues rooted in underdeveloped feeling/emotional intelligence with J stereotypes. maybe they are indivisible, to you, because J = Fe for you, and you don't like it. but i don't see that as a necessary relationship or an accurate categorization.
the representation of e5s as emotionally underdeveloped is not meant to be a particular attack on you but is meant to be an interpretation of the e5 category in generality, in all its frustrating moments. it's my reading of e5s, who systematically struggle with these issues, who are terrified of overwhelm and lose their center so easily. centering is something only which emotions provide, mediating between sensation and ideas, body and mind. centering can not result from a fixation on p or j perceptions, on outside or inside, whether they be endless narratives of what is possible or endless mirrors to reflect oneself back to oneself. choosing one instead of the other is like choosing to only accept either time or space. and furthermore, centering does not just happen in the mind between abstract j and abstract p but between their dynamic territorialization of the body and the body's upsurge through the organization emerged already.
emotions, grounded in monitoring social relationships blending and binding us together, embedding and embodying the constructs of each other into our own worlds, help us assess the strength of relationship from our center rather than an objectively measured one that substitutes selective mathematical truths over those that we can fully experience for ourselves, that we can only fully experience when we leap into who we are as well as what is arising for us. in my estimation, then, it's more about choosing qualitative methods to balance out quantitative ones, whether that be Fe/Ti or Fi/Te. without them, you can never know yourself, because your self is only bound through relationships with others that emerge as priorities for you to offer self-care through a process of giving and receiving care with and for others. that build attachment, attraction, a kind of bond, a cycle that offers to help stabilize other cycles.
for Fe e5s, staying with their own experience does not mean fixating on specific stories but means softening their focus not just to take in the whole in highest resolution but to feel out and balance the pertinent weights of the relationship, checking in with themselves by sympathizing with the experience on the outside to draw them into the body of the experience as a broad site rather than strictly a specific, instrumental one. not expanding their minds into the whole of the space of the world but taking in the whole of themselves and using that as a site to relate to the world, having a sense of home, finding a balance in the leverage of Ti, of one's own direct experience, with the ability to open to themselves, to fold themselves, by feeling out what it is like to be a thing like themselves in particular moments, exploring their own intensional structure, to feel out the biggest pieces of who they are and provide a sense of intention to their own awareness that is beyond the difficulties of determinism but instead allows their own internal structure, their own internal hierarchy of values to allow them to let go of the at times pedantic e5 retentive grasping qualities that present themselves when their various relationships with the world are constantly in flux and perceived as threatening amidst the moments of catastrophe that demand deeper revision and register as a discomfiting sensation of unpreparedness.
in my understanding of the metric of e5 development, the more clinging to an idea of self, seen as what the world is rather than realized as what one feels, even when it harms oneself and others, the more unwillingness to submit to uncertainty (for one can have uncertainty of the world or uncertainty of oneself, and both sides need to be open to be dynamic and adaptive; and truly so, not just according to the image or the narrative provided and fixated upon as a way of self-justification, which i have observed quite frequently with dug-in e5s in the "NO" phase, including myself). the w4 adds another layer, which has to do with feeling afraid that one will abandon oneself because they will not be able to accept themselves as they are if they truly see themselves and truly see their effects on other people, instead relying on the art of disconnecting and flying into a rage when that disconnection loses its solidity and one must show what one truly feels to others and to oneself.
long story short: 5s misperceive their feelings as threats.