Any dog can be rehabilitated!! Or at least the vast majority of them. Just might take a little more time now. But he’s young still so it’s still possible. Especially since his seems to be more fear based rather than true aggression or whatever. I think increasing his confidence will help a lot too. There’s lots of activities to help with that. Scent games/nose work, agility, trick training, etc. and lots of other stuff. And slowly increasing his exposure to strangers, even if you have to start from a very far distance where he doesn’t react and slowly move forward. Treats/reward when he’s calm or have people toss him treats from a distance. High value stuff like meat or cheese. It is possible but will definitely be work. I’ve known reactive and fearful dogs much older than him that have gotten better or at least made improvements but it does take determination and management to prevent him from going backwards on his progress while you’re rehabbing him. Keeping him out of certain situations unless you can take the time to train/actively work on it, etc.
And the pictures didn’t attach for some reason.

but I bet he’s cute!! Good luck with him!!