I more or less just came into my 30s and I spent my 20s pretty much exclusively on computers, studying and working and playing. Computer were pretty much 95% of my life. Last time I changed job, I more than doubled my after-tax salary and I have not once had to go through the process of really applying; whenever I showed up to HR things were pretty much decided already in advance, they just had to keep up appearances. I have always been the guy everyone goes to for help, I have more than once fundamentally changed the way people work, think and approach problems for the better. Where I have worked for the last 5 to 7 years, I am pretty much the last line "of defense", so to speak... because every time something stopped working and I could not figure it out, it would go on taking the support team of one of the biggest names in IT literally a year trying to pinpoint the issue only to not being able to come up with a solution in the end. This is not meant to boast, I am working towards a point:

So I would say my "career" is there... yet my personal life and emotional happiness is in complete ruins; while my age and point in career match at "30", emotionally and as a person, a human being, I feel like I am 12. I feel like I have completely wasted my 20s, I have never had a chance to actually grow up, I just worked on "career" which is what everyone told me to; the rest of the time I sedated myself with video games and food and otherwise spending the money I had made to numb down any and all bad feelings. I don't think I could ever get these 10 years back and grow into a strong minded, healthy human being now that the time is gone. Everyone at my age now is lightyears ahead of me both emotionally and in terms of experience and other skills.

That is why from my own experience, I cannot imagine having the opposite "20s" to be ANY worse because at least if you "wasted" your 20s, at least then you had fun and had good moments to think back on and you matured as a human being but you got something out of those 10 years and your 30s are early enough to be working on "career" with all the skills and the strength you gathered by the experiences you made in your 20s.

For me, now, I feel completely stuck and wasted, at a complete emotional and existential low point of no return. I have to try and use what little energy I have left to battle against all sorts of addictive behaviour and means of escape that I developed in those lonely, hard working 10 years. Whatever money I am making does not matter because I don't really get anything valuable and truly good from it. And even if I desperately tried to change now, I would have to invest all that energy while everyone else is free to use the same energy to lead a happy and fulfilled, enjoyable life. I just cannot win anymore.

If I could do it over again, I would do nothing but drink, party, meet people, be BOLD and strong, teach myself more about computers and do all that in a foreign country and develop a personality before anything else. Go play in your 20s, everyone else is pushing you towards "career" anyway so at least you yourself need to take very good care of yourself as a human being and develop that side and make sure you get enough "play".