It sort of *is* political, and also involves religion, because the thing stopping the Queen from appointing William as her successor is the Act of Settlement of 1701.
That law not only specifies how the heir apparent is determined (and no, the ruling monarch does NOT get any say in it), but also strikes from the line of succession any Catholic or person married to a Catholic, and also specifies that male issue precede female issue, even if the female child is older.
There is quite a lot of controversy in the UK over the Act of Settlement's provisions in regard to Catholics and women, and there has been a lot of talk lately about amending it to eliminate those provisions. I don't think that it is likely to happen in the present Queen's lifetime, however. (I won't go into the reasons why, as that would be getting too political.)
Charles is staying right where he is, and unless he predeceases his mother, he will one day be King. What the Queen is doing in terms of putting William in the limelight is simple PR -- he's popular and good-looking, so he makes a good public face for the family business, and I'm sure that his father understands that. There is a wide gulf between this and actual abdication, and I wouldn't be placing bets that the Prince of Wales would do that for anything less than a catastrophic health reason (his own health, that is.)
The Queen will still open Parliament and handle the Red Boxes, and if she gets to the point that she cannot do those things, then the present Prince of Wales will be the next one doing them.