Thank you for for raising awareness about this OP.
I used to work for a charity that rehomes hens from commercial farms and we rescue hens ourselves. Just to address some misinformation posted in the comments:
For everyone saying that the OPs hen just looks like she's going through a moult - this is absolutely not the result of going through a moult! Our girls moult yearly in the autumn and their feathers look a little sparse, sure, but they are not bald. Hens from commercial farms look like this because their feathers have been pecked out by other hens. Chickens are intelligent and form flocks, they can recognise up to 90 other individual hens. The trouble is when there are thousands of them, they can no longer establish a 'pecking order'. Coupled with boredom from not enough enrichment, and everyone becomes fair game for being pecked and attacked.
A couple of posters insinuated that these ex-commercial hens were just old. Commercial farms, including free range ones cull hens at eighteen months old when their eggs laying declines, in order to make way for new stock. Charities like BHWT, chicken rescue UK etc. work with the farms to try and rehome these hens where possible. The charities are usually required to pay the farms for these hens however, so I'm not convinced the farmer does this entirely out of the kindness of their heart. Despite charities best efforts, less than 1% of commercial hens are able to be rehomed - there just aren't enough homes for them.
Someone said that keeping caged or battery hens is no longer legal in the UK. This simply isn't true, they have just changed the name to 'enriched cages'. This 'enrichment' usually consists of a small grubby dust bath in one corner.
The conditions in some of these farms are truly appalling. It was commonplace for us to take receipt of hens and discover that several where dead or close to being dead. One little girl I personally rescued from a rehoming day had such a badly damaged leg that I thought she would have to be pts. Fortunately it was soft tissue injury, but her leg was black and blue and took months to heal. This is because commercial chicken keepers commonly grab hens and pick them up by their legs when handling them - wildly inappropriate and cruel handling practice.
If people want to eat eggs that's absolutely fine and their choice, but please don't try to justify that choice by spreading false information to trivialise or deny the hell that most commercial hens are living in.