No, I don't think we can fire Miles now. He's "earned" another year. Or we're stuck with him another year. However you want to frame it.

We should have gotten rid of him last year when we had the chance.
Miles two "good" years were very similar - get hot behind a great slashing scorer and a stretch 4 who is shooting well, take advantage of a weak conference schedule. Big difference is the other good team had a couple really nice wins and this year we avoided a really bad loss. I would think if we end up in the NIT we can at least get a post-season win this year.
If those two were his good years and the other four years were closer to .500 seasons with a couple NIT wins in the mix, I don't think that would be as bad. But the fact that he's been historically bad in four years and still can't have us run any semblance of an offense in year six doesn't make me hopeful.
I didn't want to say anything lest I be accused of just looking for any reason to be negative. But this year has the same feeling for me as 2016 under Riley. The results SEEMED to be better to some people but we got a break with a soft schedule and played just well enough to win a decent amount of games. But when you look closer you can still see the same problems lurking right under the surface. And when you have a chance to look back on it may be more obvious that the "progress" made was only slight at best and when we revert to how things usually are we won't like it much.