I find it helpful to remember that bhikkus needed to present their activity as inherently virtuous, because in the time of the Buddha, people commonly believed that the merit gained by giving was proportional to the moral rectitude of the recipient - in other words, the laity would give food to begging monks only if they thought they were virtuous .... you can see how the monks needed to be, or at least be seen to be, 'morally upright', and it is a small step from there to claiming that their path was in fact a path of progressive moral purification, leading to moral perfection.....
However, no conspiracy theory seems to be enough to account for the fact that, in the suttas, enlightenment is virtually
always expressed with some species of 'limited emotional range' model. As Daniel says in MCTB,
The Emotional Models are so fundamental to the standard ideals of awakening as to be nearly universal in their tyranny. You can’t swing a dead cat in the Great Spiritual Marketplace without hitting them.
And the extreme opposite view, that the emotional life of the enlightened is no different from that of 'ordinary worldlings', just doesn't quite ring true. Speaking personally, some permanent change
has happened. My mind is no longer 'sticky' in a way it was. There is a certain kind of suffering which accompanied that stickiness which is now absent. And there are certain kinds of emotions that followed from that stickiness which cannot, i believe, now arise. I do not feel that my emotional range is 'limited' (which somehow implies a cage), but neither can i imagine any conditions that could possibly result in my falling into certain kinds of grasping states.
I can certainly experience anger ... i have children, and manifesting anger is pretty crucial. i am not exactly putting it on, they would detect the falsity, but on some level it is a free choice, a kind of tactical decision. when it has done its job, it vanishes completely. in the past, though, i have been consumed by anger, without any sense of choice, and it has lingered like the after tremors of an earthquake. this is one way my emotional life has changed as a result, i'd say, of having no fixed point of selfhood to which i am compelled to return.
I am no scholar, but one of the interesting things about the Suttas is that some are much older and less 'messed with' than others; the Mahaparinibbana sutta, for example, is very highly edited, and i have no qualms whatsoever about rejecting the claim in there that the stream entrant has 'perfect moral conduct'.... after all, that even flatly contradicts other (and earlier) suttas.
So assuming the 'limited emotional range' model became exaggerated over time, perhaps there is a more sensible view in the older suttas? One of the terms which seems to crop up in the earlier suttas, but less in the later suttas/commentaries is 'asava'. Enlightenment is often identified with "the destruction of the asavas" (or, more particularly "knowledge that the asavas have been destroyed").
Asavas is most literally translated 'influxes', but I like the more psychological translation 'inflations' (from Rune Johansson, "The Dynamic Psychology of Early Buddhism"). Inflation is a well understood psychological process (eg see "Ego and Archetype" by Edward Edinger) .... the interesting thing is that it is essentially concerned with one's own idea about one's self .... so it seems quite reasonable to say that an Arahat should at least have left behind the emotional complexes driven by trying to define a self-view.
There are a few more points i'd like to make to refine the above, but i'd best leave it there, as long posts don't really belong in forums imo.....
TL;DR .... maybe there are some classes of overwhelming, self-obsessed emotional states that an arahat will not experience, at least once they have done enough 'review' to have truly settled into their arahatship.