The gas is untreated and still contains impurities and water. This water will freeze around valve internals and instrumentation rendering them useless. Ice can be removed by methanol injection, but large amounts will be required.
I know all that stuff my family has been in the O&G business since the 50’s. Flaring is the cheapest way of maintaining the wells. They are giving up production at the end of the life of the wells to prevent damage that could destroy them now.