Pensions are so overrated

For context I live in the UK.

Right I'm 23, so my youth and "abundance of time" might be blinding me, but I cannot understand why pensions are seen as this obviously good financial decision for anyone and everyone no matter their circumstances. My god, the amount of elderly people (50+) telling me I should start investing in my pension now.

Lets think of the basic concept, you pay money to the government and they keep your money for you so that after retirement, they'll pay it to you as a salary so that you survive until you die. Oh, and also, the you don't pay tax when you contribute to pension. BUT, you do pay tax when you take your pension out after retirement, so great I guess that benefit is just for show?? A song and dance??

The fact that I'm paying my money, to the government, and I cannot, under any circumstances (apart if I get terminal cancer or something... great) access this money, and I'll only get it, when I'm 67+ (or whatever retirement age is) just sounds like a ridiculous financial decision.

Let me list my arguments:

1) I don't know how old I'll live to. I'm "saving" money for 40+ years down the line! Who knows if I'll still be alive, why should I live frugally now in my 20s so I can maybe live comfortably when I'm 70? It's absurd!

2) I need the money now. Like seriously, especially in our current economy. I can say with certainty, I need this extra money more now, than I do when I'll be 70.

3) It's assuming I can't manage my own money or get my own income at 70+. Think about it, why is this system even there in the first place? Because the government assumes, most people won't be able to save money for their retirement, without their help. Why is the government holding my money and giving it back when I'm old like some parent giving their kid pocket money???

4) The government will pay some money regardless, no matter if I contribute or not. So why is everyone acting like I'll just be homeless at 70 if I don't pay into my pension??

5) It's more suitable for some careers and less for others. Work a manual labour job? You're going to need an early retirement due to a strained body, so a pension is interesting. I work as a programmer, I can continue working for a long time realistically, well into my 60s, with a growing salary, job opportunities and prospects, why would I need a pension??

So please, can someone explain to me, why every one (including office workers) is pressing 20 year olds to invest heavily in their pensions???? I opted out of my work pension scheme, saving an extra £100 a month. Get out with your pensions.