Could you make an argument for bothering to fund 401k + IRA/Roth at 20-something? If I'm trying to get fuck-you money by 40, don't I need every dime in order to get there? My nest egg is in plain old savings right now because I view it as personal runway.
If you plan on being alive at 65, then yes you should. Both are fantastic investments because of the tax free growth. Basically everyone should follow this pattern with extra money they have:
1.) Max out employer matching in 401k
2.) Max out roth IRA contribution (in most cases, sometimes you might want a normal IRA)
I don't understand your implication that striving in a career endeavor requires that you spend all your income with nothing going to savings. If anything, healthy savings will allow you to take advantage of an unexpected opportunity, and/or lessen the impact of an unexpected obstacle. This 'backup plan' will also make it easier to take risks without having to worry as much about the potential for failure. In other words, savings provides you with options.
But that's in terms of general savings. For retirement more specifically, you should definitely start now if you can afford it, due to the effects of compound interest. Try playing around with an interest calculator[1] to see why. But perhaps the best reason is that once you're 40 and have had a few curve balls thrown at you, you'll appreciate that regardless of how things turned out, you'll have put yourself in a good place financially for the long-term.
For the record, I'm in my mid-20s myself, and across my Roth and my employer's SEP-IRA, around 20% of my income is going towards retirement (with other non-retirement savings on top of that). I've set up my direct deposit such that the Roth contributions are totally automatic. It just gets dumped into three index funds: US Stock, Intl Stock, and Bonds. I basically never need to think about the accounts except when rebalancing. It's nice.
If you can't afford to fully fund your 401k without thinking twice, you have bigger problems in your financial setup. $16,500 out of a $100k yearly salary is just stupid cheap.
If you are not making $100k+, you are not going to have fuck-you money by 40. All the Facebook stock in the world still requires a liquidity event, which is unrealistic at the current valuation.
