In my own experience, life as a semi-hermit (I've never gone all the way) has its ups and downs. I didn't miss trying to make small talk with co-workers and fellow students, enjoyed not having the external pressures of work or school life. I like being able to manage my own time, to put my energies into whatever projects, tasks I want to work on.
On the other hand, if you take it too far, do it too long, you run the risk of getting to a point where life starts to feel a bit meaningless/pointless. Perhaps ultimately life really is those things. I think it probably is. Nevertheless, it remains important, for our own human flourishing, to make meaning for ourselves, and that involves interaction with others, and for me, interaction with people specifically. I love other animals, but I need to connect with people. I certainly need time away from people, too, sometimes, but it's a question of balance.
Direct action is always the clamorer, the initiator, through which the great sum of indifferentists become aware that oppression is getting intolerable. - Voltairine de Cleyre