The attached article was written in the States, so there may be some terminology you are unfamiliar with. Basically, they are talking about the benefits of saving for retirement as soon as possible, and the impact it has on the long term fund.
Basically, by starting saving at 15 instead of 25, the end result is almost a doubling of the final investment or pension fund - now that would have an impact at age 65.
Frequently, at Serenity, we come across grandparents who want to do something for their grandchildren, to help them in the long term, but not to give them money now. The same principles apply here in the UK...
By paying in £3,600 a year to a grandchild's pension from when they are born to 18, would (based on Hargreaves Lansdown's pension calculator), give a fund value of £831,000. Now take that figure, and leave it invested to age 55 (presently the earliest we can access pension funds) and with no further contributions, the fund grows to £1,140,000 - now that is quite some start in the second half of life.
Of course, pensions are surrounded by ever changing regulation, but if you want to leave a lasting legacy for your grandchildren, which, later in life they will look back and thank you with great fondness, this may be a route to consider (and it won't be wasted on their first car, laden with fluffy dice and multiple spoilers.
if you'd put that hard-earned cash into a retirement account instead and let it gather interest through the years, you'd be high-fiving your 15-year-old self all the way to the bank.