I can understand why people who post here (me included) aren't familiar with him but it is important to remember that he isn't an unknown and is actually a bit of a casting coup. He's one of the stars of a show that's hugely popular worldwide, he's had three BAFTA nominations and has 2.6 million followers on Instagram*. They've basically snagged him just before he got to the point where spending three years in Cardiff wouldn't be attractive to him.
*I wish we didn't live in a world where that matters but it does.
*I wish we didn't live in a world where that matters but it does.