I admit I am fascinated, seriously, by the hair-splitting that the answer to "can a minor consent?" differs depending on the subject. Not saying I know The One And Only Answer, but the flip-flopping depending on the situation is... well, fascinating to observe.
there's a lot of self-inconsistent rationale when it comes to this, and not easy answers. you're stuck weighing the person's rights with their capacity to make decisions for themselves...sometimes permanently life-altering ones. the law clearly applies broken rationale to it; people can get major surgeries of solely their own volition for years before they can legally decide to consume alcohol, and in both cases it's the state deciding for them what they're capable of/responsible for.
the other problem is that treating the topic consistently implies either majorly violating norms wrt age of consent, many which exist for good reason, or to effectively treat obviously capable people as sub-human in terms of reasoning capacity until they hit an arbitrary age. i'm not comfortable doing either of these things. i could be convinced that the drinking age for alcohol be lowered for example, but it seems like letting 20 year olds sleep with 13 year olds will cause way more harm to people's lives than good. even if we then turn around and let the 13 year old decide on medical procedures that could also seriously alter their life. in the latter case, both procedure and inaction are choices with consequences that last, and someone has to make that choice. even if the person in question isn't fully equipped to evaluate it like someone more experienced, it's hard to buy that they shouldn't have a say in what is more or less a forced choice scenario wrt their future.
i find myself questioning the rationale for letting parents block it even if we replace "abortion" with "elective surgery that improves qol", like correcting an issue that lets the minor walk properly or something that the parents don't want done then. we're going to tell that person they can't get it? maybe, but that doesn't feel right.
You think going to a concert is a better comparison? Even if we consider this, are you saying it would be appropriate to criminalise a child's friends who take them to a concert, in the land of the free? And to complete the analogy, this is locking someone up because they allowed a child to use their phone to buy concert tickets.
you're being fairly loose with "friends" here. it is easy to envision scenarios where it looks bad, and in many cases probably will be bad. law has to draw the line somewhere. like when the "child" is 10 and the "friend" is someone many times their age that the parents don't know. very different look from when everyone going to that concert is the same age or close.
Edit: Just to be clear, I'm saying embryos/fetus fail to qualify sufficiently for the categories children/human imo.
this has always been the fundamental question, even if courts and many people don't want to go there. everyone draws this line at some point, and the question is where the law should draw it. at some point, the fetus becomes "legally human". for most people, this is before birth...but how much before varies greatly and there's a lot more emotion in it than there are objective reasons to pick any particular point to draw the line.
if the minor can't consent to sex, i don't think it's weird believing that they can consent to not having a child
they can also (by logical extension) consent to having it, unless you want to legally force abortion in this context. it's one of those "even if they're too young, this is now a forced choice and it's going to impact the rest of their life either way" scenarios. sucks that the scenario exists, but since the choice has to be made, the person living with the consequences should probably have the most say.