Risks and safety for horses

A big reason people don't keep horses in a herd is because they are scared of their horse being injured by other horses.
The reason freedom is denied to some horses for a part of a 24 h day is to keep them "safe".
People remove/fence off trees shrubs or even dam's to "reduce risk of injury" from branches, sticks and...mud?
One of the main reasons some people are hesitant to give track life a go is the extra fences and again increased risk of getting hurt by those.
To keep horses safe and reduce risks we keep them in as flat as possible and small as possible, square as possible paddocks or worse, stables.

At what price though ...

I'd much rather know my horse has a fulfilled life, is able to move freely, has mates, is strong and healthy mentally and their MAJOR needs are met, than trying to avoid very uncommon fatal injuries by a herd member a tree or a fence.

Not saying they don't happen !! But also wondering why they are happening sometimes?
Could it be that if a horse never ever has to look where they're going and coordinate that with lifting their feet, adjusting their speed or avoiding a poke or scratch, how can learn then!? If they're in a stable for 12 hours then let loose, well of course they could get over excited and run through a fence accidentally because they hadn't moved for ages(horses sleep for 20 min at a time, they are prey not predator). If they have been growing up in solitary then meet a horse in a paddock for the first time and have to figure out how to communicate and read the other horses cues but isn't given enough time to figure it out, how will they ever be able to?

To live a good life we all have to take risks.
I mean we as horse riders take risks of literally dying every time we ride our horse, somehow we're fine to take that risk for our happiness.
But we can't do the same for our horses?! Why ?

Horses need other horses, horses need to be able to move freely horses need stimulation and an enriched life. Even if that means they COULD get tangled in a fence, take a kick, get hit by a branch or have scratches every now and then. I'd always choose to have trees and a track with mates over a sad life with no risks. Actually for me the little nicks here and there from our tree branches and bushes or herd members, are great to see, like a three year olds knees you know they have learned how to ride a bike or jump over stuff, climb and fall but are free and able to learn, explore, have fun and grow mentally. I'd never deny my child to go out because of risks of injury, I won't be doing this to my horse either.

It totally SUCKS if they do get seriously hurt, my horse broke his leg in a big open flat paddock, it was horrible and I cried for weeks, but things happen unfortunately sometimes.
We can always make it safER but for me it's not worth taking away basic needs.
Of course we have to make our personal choice what risk outweighs what benefit ect