~snip~
Well, this may work for him as he is saving 500 euros every month from his salary and converting to bitcoin. This is a good amount and for sure he can have an early retirement but most of us cannot put that much money into investment in Bitcoin on a monthly basis. The secret here is that if you have more money for bitcoin investment, you will get more profit and hence you can plan this early retirement. Otherwise, with less investment, it will still be good but the money won't be enough to feed you for many years.
The key thing is that anyone can start saving in Bitcoin.
If you simply put aside an amount you won't need, and get Bitcoin with it, you will probably end up in a better situation in the future.
I think the key thing here is that Bitcoin has made investing mainstream.
Now anyone can invest by buying Bitcoin, whereas in the past investment was usually seen as a more complex and expensive thing.
This has led also to plenty of apps and companies that offer micro-investments these days, but those didn't exist pre-Bitcoin (I think).