No, I doubt many people do.
My point was her age at the time allowed her (in my opinion) some adolescent 'freedom to be wrong', to have made the wrong choice, to be mistaken and probably misled etc. However with her (relative) maturity/and experiences she has had, should come genuine regret. All the more important because she would be about to enter UK society once more, to take her place in that society, one she jeopardized when she was still basically a child. The Home Office has to be sure she is no longer a danger to herself, or anyone else.
If her involvement with Isis had taken place in this country she would probably (but not necessarily) have been imprisoned here that is true, but she might also have faced deportation there after.
It is not being imprisoned that is the issue, its being free to enter a society she once shunned!