I don’t like to call it hyperfocus because of this narrative that it is a “superpower”. It is still inappropriate focus. Barkley calls it “perseveration”, which seems more accurate to me. Yes I can get things done, but at the cost of an inability to observe time and by causing me to forget everything else, including food.
Medication has been wonderful but it isn’t perfect, and I find that it takes work for me not to overcorrect and lapse into too deep a state of focus.
As for exhaustion, I used to get that when I was undermedicated. At the appropriate dose, I’m fine. My “natural” state of perseveration of focus usually comes with much larger baggage (eg. blind panic at a looming deadline) so it’s hard to ascribe the exhaustion to the act of focusing.
Some ED on Concerta or Vyvanse. Not an inability, more of a sluggishness to achieve a good erection. However, this is now in the back of my mind, so it impacts my drive a bit as I’m conscious of it.
In short: not perfect but not ruinous either. I’m also 44 so it could be a little more noticeable for me than for a younger person?