Since my father is now legally blind, he refuses to bring in home care. How do I convince him I am not forcing him?

Of course he does, and he'll likely dig in like a tick too. He won't accept help, he won't want to go out, if he's like my father he won't bring a cane, much less use a white one, or do anything to face / deal with the blindness.

You can't force him, you can nudge, push, cajole, and maybe, over time get some progress. If he's like my father, it took years to get him to go to a program offered by the VA that seemed to me like it was incredibly valuable for the blind. He made up all kinds of excuses and is still one of the most stubborn people I know. As one of the posters mentioned, it has to get bad enough, or something bad happens, that they really have no choice.

The problem is, the earlier they accept help, the easier it is to maybe learn some skills and techniques. If they wait, well, every year it just gets harder until, maybe, it doesn't even matter anymore.

I'll be honest and say that my father can really piss me off (you can tell because I come here and write a few posts). Go down this road at your peril.

Seems to me the two youngest are going to have to step up. They don't have to do anything they don't want to but need to make him aware of what they will or won't do. At 80 I don't see why he can't get help in learning how to get around the house without help. Blind people do live alone. Its a matter of keeping everything in its place and learning how to be safe. He will be much better learning how to do for himself. Your County should have a Disabilities Dept that can help him. Your State should have a Dept for the blind. His Ete Doctor may have information.

80 and legally blind. Generally speaking, seems like he could benefit from being in assisted living. How bad is his sight? Can he still see enough to safely navigate? Is he safe home alone?

You probably can't convince him of anything, right? So, depending on what level of care you are currently providing, you can push back and set some boundaries and thereby "force" him into using home care services, etc. As long as he is capable of coordinating something like that on his own. At 80, it's questionable, depending on the person.

Advise him. Let him choose.

Three choices Dad;

#1. Age in Place - as King of your Castle. To do so, accept your difficulties. Collect your team of hired help & let them in.

#2. Age in Place - as a stubborn tyrant. Have your rights, to do as you please, even if it means you & your home become unsafe.

#3. Age in a Care Home - accept your difficulties & choose to live where help is provided.

So 1 & 3 involve him accepting where he is life - accepting CHANGE. Then he can plot his own course.

2 is NO CHANGE. Usually folk live that way for as long as they can, until a crises happens. Then they often get forced to change, to choose #1 or #3.

Best of luck!!

If you father is legally blind, he probably doesn't need to be living by himself anymore, as that is an accident waiting to happen. Unless one of you siblings are his POA, there is not much you can do except wait for that accident to happen, and then you will be able to act on his behalf.
In the meantime, does he have any neighbors that can at least come and check on him occasionally? And perhaps it might be a good idea to place security cameras in his home that you all can access from your phones, so you can at least check on him when ever you want to.
And other than calling Adult Protective Services to report an elderly person who may be in jeopardy, I don't believe there's much more than you can do, right now. Best wishes.