I've not read the whole thread, but thought I'd add my experiences.
I am a vet. My 3 mini rexes were in a run in the garden, with my housemates in the house keeping an eye on them. A fox entered the garden, grabbed Indi by her hind foot and bashed her against the run bars trying to get her out. My housemates got to her in less than 10 seconds, had to kick the fox to make it let go, but it had already dislocated all the bones in her foot below the hock, broken her jaw and bruised her eye.
Miraculously, she survived the stress and pain and started eating again once she had been given high strength pain killers (buprenorphine) despite the broken jaw, as it was inoperable. She underwent two surgeries to fix her foot and was hospitalised for 10 days in total (would normally be longer but I could do the daily bandage changes at home). Just to stabilise her and take x-rays to determine the damage cost nearly £800. In total it cost me nearly £2k and she is still recovering. She can use her foot quite well, can run and binky and periscope but cannot bend her hock fully and will get arthritis in the next few years. Her teeth are in-line despite the broken jaw, which has been left to heal by itself, but will probably need dental work in the future as its unlikely to be perfect. There were complications with her catheter and she could have lost an ear. She has scars on her foot and the hair may never grow back properly, which is a major issue as she's a rex. One of her toes points slightly downwards, which may cause issues with sores and mobility.
For me, I spent days in tears on and off, hours going back and forth to the vets, changing bandages and giving medications. It totally dominated my life for 8 weeks as I nursed her back to health. It was incredibly difficult to concentrate on anything else and I had very little time or opportunity to do anything else other than work during that time as her care was so time consuming. At least twice the fox came back to get her, even trying to get into my house where they were in the lounge recovering. The other 2 rabbits suffered stress, reduced appetite risking stasis and social confusion without their leader bunny. The bond may have broken leaving me with a poorly solo bunny and potential injuries if they had fought.
Indi was incredibly lucky. Most rabbits don't survive the attack. Those that do, often can't be treated and/or people cannot afford the care.
Indi was in a run and supervised when the attack happened. Why would you allow your animals to be free range and therefore at greater risk, when the health and welfare of the rabbit is at risk, and the financial and emotional impact on you is so massive? It just isn't worth the risk. It took seconds for it to happen, and seconds to rescue her, but the damage was done. If you aren't out there in the garden the entire time then there is nothing to stop this happening, or worse, to your buns