I think there are some other factors behind this delayed adolescence that are not addressed here.
The family unit itself has a much bigger impact I believe, than what is being addressed here. At least it was for me and it is for my friend who is currently going through "failure to launch" right now.
When I was a teen my mother instilled in me the expectation that I needed to be perfect and that any failure on my behalf, any defiance, was a sign that I was "hurting her", "being ungrateful", "not loving her" etc. So I didn't rebel. I didn't party. I studied hard and I tried to follow all the rules that she set for me, including the unreasonable ones. As such I didn't have a boyfriend either until I left home at 22.
One might consider that delayed adolescence. But what it was was more the fear of doing the wrong thing as seen by my mother and being punished by the person who I loved the most.
Fortunately when I left home (due to abuse) I had already graduated university, while I didn't end up working in the role I had studied for I had to work minimum wage for a while, working 3 jobs to make ends meet - and doing that actually forced me to find a different career that actually suited me better, which brings me to age 28, making 6 figures, in a way better financial position than I expected to be at this stage of my career.
In a way, while my mother was the cause of my delayed adolescence she was also the catalyst for my breaking free as I couldn't deal with her emotional abuse anymore. And her estranging everyone from me for a couple of years was really tough, but I grew very independent as a result.
Looking at my friends - only one of them really qualifies as "failure to launch" - she still lives at home, with her mother, while she graduated from university she is not working full time and keeps taking on additional tertiary education. I think what's holding her back are several factors, none of which have to do with social media or a culture of perceiving "microaggressions" everywhere.
1. She believes that she needs to be successful in her dream job (film director) and to have full time employment in the film industry, in order to be able to leave home. Of course this industry is one of the hardest to break into, and despite me telling her multiple times she doesn't have to start there full time and many famous directors had other full time jobs for years in other industries before making film their main career, she feels like anything less than full time work in her chosen industry is unacceptable, and becomes more bitter and self hating the longer the time goes that this doesn't happen for her.
2. She is mentally ill and stuck in a negative mindset where she believes that she will never have a romantic relationship, despite a boy in her class clearly giving her so many signals that he's interested in her she won't take a chance and ask him out. She just assumes it can't be true that anyone would like her that way and so it becomes a self fulfilling prophecy.
3. Her mother lets her stay living with her and doesn't set a date that she has to move out, making her feel like she can stay at home forever.
I think reason 1 is one of the most common reasons for failure to launch. This belief that you can't succeed if your initial plans for your future don't work out the way you intended - that you have to be successful in your chosen field of study initially, otherwise you need more tertiary education. But that's not what I have found. My current job has tangental relevance to my bachelor's degree but I actually got it through my work experience in retail sales. Life has unexpected pathways and I think a lot of youth don't realise or embrace this fact.
