Wow, OP, it really is basic parenting to have a handle on where each of your children are up to with their morning routine at any point and chivvy them along if they aren’t eating breakfast/brushing their teeth/whatever by the usual time you’d see them doing that. Teens need this just as much as younger ones (more so, in the case of getting up!). This is not mollycoddling, this is being a responsible parent and making sure your child leaves the house on time to catch the bus they need to.
Mollycoddling at that age would be setting their alarm clock for them every night, setting out their uniform for them each night, taking them their breakfast in bed, packing their school bags/PE bags for them, standing over them while they ate breakfast/brushed teeth, driven them to school each day and picked them up again even if you don’t need to etc etc. Totally unnecessary in a child without SEN and very damaging to their self-confidence.
The absolute priority for parents in a morning is making sure their child gets out of the house at the time they need to. That is YOUR responsibility as he is the child and YOU are the parent with legal responsibility for ensuring he does so. It isn’t right or OK to forget about him in the morning rush of a busy home life, not even with multiple siblings. It’s not ok to not prioritise him as well as your younger children. Apart from anything else it will be damaging to his self-esteem to know that he comes way down your list of priorities. I always wave mine off at the door, and know that I’ve done my job - they are out the house on time.
Just because a 12 year old is capable of something doesn’t mean they should be routinely doing that thing and sod any time they don’t manage to do that. Eg My 12 year old could make his own basic evening meal if he hAd to, (so if DH was away and I was very unwell it would be fine) but I wouldn’t eg choose not to make him something if I wasn’t hungry myself just because he CAN do it. Same with keeping himself clean. He can do the cleaning part, but it doesn’t mean to say that I should leave him to it and remember when to have a bath/shower. Teenage boys are known for being soap dodgers, part of parenting is to give them a nudge regularly to have a bath or shower. Or switch his light off by 10pm latest. Once these routines are ingrained in their psyche they shouldn’t have problems continuing with them naturally once they’ve reached young adulthood. Till then we are effectively their “coach”, teaching them how to have good routines as an adult. Look how birds and animals do it. They are close by, checking that their offspring ARE catching that worm or managing to get their share of the antelope. You, OP, need to be the mummy bird standing near checking your DS is doing what he needs to be doing at the time he needs to be doing it. Not forgetting about him completely, expecting him to get on with all of it on his own. Otherwise he’s just a lodger in your house.
And I agree with others that kindness towards each other in a family goes a long way. If for some reason MY alarm didn’t go off but the kids ignored the fact I wasn’t up and went on their merry way to school, making me late for work I would be kicking myself that I hadn’t raised such inconsiderate and selfish children.
It’s just looking out for each other, and you need to start doing it to your little boy. At 12 they generally ARE still little boys. And I work in a boys secondary school so see a whole RANGE of boys and and parenting styles from mollycoddling to neglect. I would be raising an eyebrow if a 12 year old child told me they had to get themselves up every morning even though their parent was around at home. It would cause me to look out for other signs of possible neglect to be honest eg scruffy/dirty uniform, regularly not having money for bus or lunch, not equipped for lessons, not turning up to school and parents not calling school with a reason for absence etc (You come under this last one....)