I don't think one can read anything into how he will be as king from what he does now. Whether or not it's wearing thin as a reason, he does still have young DC and it's not unreasonable, in fact I think it's a good thing, that they aim for as much normality as possible, with both parents fairly present and involved in home life, dropping off at weekend activities and so on.
None of which means he won't fully step up when required as king, or if Charles lives a long time, to act more for Charles once his own DC are older.
Caveat: I have young DC and I find life exhausting. If I could minimise work and use staff, I absolutely would!