Since there is a limited window in which brain plasticity is at its peak, catching up at university isn’t an option.

I call bullshit. It may be true that there is a peak, but it’s not like after that peak it’s hopeless… I’m 50 years old and I work a job where I literally have to learn an ever changing product in order to support it, and I’m doing fine, I just got promoted to senior so I’m teaching the new hires. I haven’t even been there 5 years yet.