I did this, actually! When my mom died, I moved in with my father because I didn't want him to be lonely. I was..in my mid-20s, I think? And he was in his late 70s. For me, it was mostly positive--it reduced my living costs (though I was very not frugal at the time and blew way too much of that money on things that I now regret), he cooked dinner and drove me to and from the train station, we went on trips together...we were good company for each other, as we were both quiet and bookish, and we never fought. The one downside was that it let me lurk in a sort of half-adult comfort zone, and my life stagnated quite a bit. After he died, I ended up in another "stay to support" living situation, and it's only now, about 2 years after getting out of that, that I'm starting to feel like I'm living my own life.
So I think it would really depend entirely on your relationship with your dad, and how much of a life you would have outside of that relationship. It's probably not worth it if there's likely to be frequent tension between the two of you, or if you'd feel smothered. Otherwise, it could be OK, or even really good.