Well I googled Hoyle Ing Dyeworks and found the following article from 2016:
https://www.examinerlive.co.uk/news/west-yorkshire-news/linthwaites-hoyle-ing-mill-torn-10867076
It was supposed to be turned into "13 luxury homes" and work was supposed to start "the next few months".
Clearly it's all fallen through, hence the reason you were able to still explore in 2021!
They ran out of cash, it does happen often.