Well yes, people actually have. Quite a lot.
en.wikipedia.org
Which is a good thing, as when the state pension was introduced, the population of the UK was about 40 million. It's now over 67 million, so we've somehow managed to find work for 20 odd million new people since the state pension was introduced.
This is the problem with the state pension system as it currently stands though, as when it was introduced there were a small number of pensioners living not very long in retirement, and their pension was paid by a very large working age population. Now, things have reversed and the retired population is not only much larger as the boomers enter it, but they're living longer in retirement. The generation behind them is smaller so we have much less working people to pay for a much larger number of pensions.
No political party wants to tackle this problem because of the aforementioned voting propensity of pensioners and the media-friendly cries of it being so horribly unfair "I've saved all my life down t'pit you know..." etc. etc. Maybe if the governments of the last 100 years had deigned to design pensions more like an actual bloody pension where payments go into an actual pension pot then things might be different, but none have.