Alternatively how about you play for your country that you were born in? Crazy idea i know but everyone is born somewhere. This business of people choosing their national team in whatever sport seems much more common these days than it was 30 years ago. Final point on Rice, I am not so sure he was so emotionally torn as he thinks. Possible Southgate has been in his ear and said you are good enough to play for England and we got to the world cup semi final. You are less likely to get that chance playing for the republic. A couple of decades back the ROI team were jokingly refereed to as England B. Not all of them but i suspect many players who thought they wernt good enough to be picked in the England side still wanted to play internationals and suddenly found a grand parent. There are loads of them.
Where you are born doesn't define your nationality at all, it's a completely random event. Raheem Sterling should be playing for Jamaica should he?
As for Rice, I don't know him. I've no idea how he might feel, but I would say it's perfectly plausible.