I'm 46, still not an early riser. I sometimes wake up early, usually due to a bit of stress, but that just messes me up worse since I can't shift my schedule backwards (jetlag going West-to-East is hellish for me). I have become more 'rigid' in my sleep schedule which is better for fitting in with the rest of society than the phase I went through in college when I was on a 26-hour sleep schedule and every 2 weeks I'd rotate my sleep schedule around (generally trying to time the period when I was sleeping right in the daytime for weekends although I'd skip classes on either side). But that rigidity means that its hard to nap (and of course if I nap a bit too long in the day then I wind up staying up until 3am, so usually if I get up too early I wind up having to push through with sleep dep all day and then just hope it doesn't happen the next day -- but the stress itself from not getting enough sleep can cause me to get up early again in a bit of a viscious cycle).
I used to think this way until I realized we program ourselves with words and chose to believe the opposite because neuroplasticity is a thing and we are way less rigid/static creatures than we tell ourselves.
I change my life by changing my words.
Edit: No idea if this is applicable/useful for others, since we are also more complex than simply linguistically programmed machines. It's simply part of my own self-programming experiments. I'm not making claims this will work for all or anyone else; I'm simply sharing my truth. I'm curious if aligning beliefs with intrinsic motivation to change sleep patterns and changing thought/behavior patterns toward morning rising could lead to it.