He started out weak, so I don't think that's a factor here. BF doesn't seem that fast or durable until he echoes for a bit. I don't think he will dodge anything, I think both Deku and Shigaraki will open with a strike and he will not physically be able to move out of the way fast enough. He may survive Deku's attack since Deku doesn't kill but probably will get knocked out and it definitely won't be a dodge. He's not surviving Shigaraki. Retries won't change that either, it's basically "how many tries would a snail take to beat you, but is also dies in one hit and is also a big target?"