Once the producer gave up continue tea making, the tea field is messed up like forest.
There might be some reasons but at least they quit because they cannot make profits as business.

It’s not easy to keep producing tea as business.
I’ve met many excellent producers and their knowledge are quite deep.
Agriculture is not fantasy like living with nature.
But manufacture to keep producing quality product with theory adjusting depends on the nature.

If utilize the abandoned tea field, pan fired tea might be still possible.
Picked some young buds and tasted.
One is quite aromatic, but another is quite bitter and long lasting astringency.