I agree, welsh rugby is in a really difficult place right now and a solution like this feels like the sort of thing that someone with no 'skin in the game' would come up with because they're obviously planning to kill Scarlets and the Dragons to roll it into Cardiff and Swansea.
Rigby is struggling for players all over the place though, the handful of people I know in the professional game (including one at scarlets who I'll have a chat with later and get his thoughts on this) have all said that things are really tough since covid, both financially but also just getting kids into the sport.