To give it a wider audience they could have a "Rugby" channel that shows both Union and league
You can already watch every premiership game on https://www.premiershiprugby.com/prtv/full-match-video/ , but how many people actually use this?
I frequently do and during lockdown, the Sale Supporters Club have been doing a watchalong every Friday night using this site.
The main frustration for me is that the games aren’t uploaded until (usually) the Monday. For games played on a Friday night, that’s an annoyingly long wait imo.
To give it a wider audience they could have a "Rugby" channel that shows both Union and league
I can see that going down like the proverbial lead balloon with the League mob! It'll be branded as a plot to denigrate the "Greatest Game"

by the Establishment, the AhEffYou, The Vichy Government, the Illuminati, Lizard Overloads, Xenu, etc...
More seriously, it would be harder to arrange the live games during the overlapping of the seasons of both codes.
The main frustration for me is that the games aren’t uploaded until (usually) the Monday. For games played on a Friday night, that’s an annoyingly long wait imo.
Probably part of the deal with BT & C5 that they aren't allowed to post the full game until after the highlights show has been aired.
If they're thinking more along the lines of a RugbyPass subscription-based online "channel" then maybe. I'm yet to be convinced these subscription services work the same way for primarily live content as Netflix does for drama/films/docs. And if even 50% of the rugby-watching public feel anything like I do about the ephemeral nature of sport then I just can't see it having a broad enough appeal.
I mentioned RugbyPass as they already are in the Cable TV market and you can get the RugbyPass TV channel from your cable TV provider in some countries.
I also think that there is also an ESPN Rugby channel available in the USA. A friend of mine in California can watch live Premiership games on his cable TV offering.
So - I think that this sort of channel already exists - - just not in the UK
You can already watch every premiership game on https://www.premiershiprugby.com/prtv/full-match-video/ , but how many people actually use this?
Firstly, you have to wait too long to watch it. Secondly, the picture quality is poor at best and laptop screens and sound are pants.. Thirdest, you cant record or playback/pause very easily. Forth, If you want me to pay say £10 a month on top of my existing subscriptions the service needs to be a lot better than the online GP offerring.