If streaming is given the green light then all the club can do is put it to the test. There would be gains from exiles/away fans and whoever else. There may be some losses from non-season ticket holders who would forgo the wonderful match day experience of EP to deprive the club of income by sharing a pass. But how many would that be?
The club would have to work out what their projected walk-up attendance is likely to be, say 3000 and by how much that may drop compared to the extra streaming income, and make a decision as to whether they gain or lose.
I don't see streaming by people using IPTV via VPN being a threat. For example I use IPTV/VPN and I've not come across it apart from NL BT games being streamed, but not streaming by NL clubs own often poor streaming service. I cannot envisage this aspect of viewing affecting County's streaming service.
Finally I would suspect town based fans who may be termed as casual/part time may be the ones tempted by streaming.