A dreadful OP, for reasons largely already given.
Your reference to the Currans is revealing. For one thing, Sam Curran isn't currently in the ODI team (he's hardly played, and averages 8 with bat and 45 with ball). But what I find interesting is that you say he was poached from SA whereas his brother Tom was poached from Zim. Surely by your logic these brothers should both have the same "true" nation, whichever that might be? By assigning them to different "true" national teams you're admitting that nationality and national allegiance is a blurred issue. People move from country to country, and have all sorts of multiple identities and allegiances, far more than was once the case.
England, and the UK, has always been a mongrel nation, comprised of immigrants and enriched by them at every turn. If players want to play for us rather than for someone else, I'm fine with that. If Renshaw wants to play for Oz, Wagner for SA, Tahir for SA, etc, I'm fine with that. Good luck to them.