As to excel - what is meant by excel in chess that means a goal is reasonable given the time or amount of focus you can put into it. In Lasker's day you could be WC or a strong 'master' and not just be solely a chess player, there
wasn't so much to learn and 'common sense' and study of a few greats
could take you a long way. You could also be a 'master' of many other things - the investment of time needed was not as great.
Nowadays, to reach a similar percentile it's a lot harder, and even those who
do/did other things often got their big chess rises before going off to do other things (Sadler
and Kamsky being good examples, but there are plenty of titled players
that work in finance for example as it pays a lot more, yet remain pretty strong players). The reason being that there is tons of theory,
lots to learn, the competition is stronger - to get there you need to spend so much more time.
It becomes a career, and sadly for most, chess' payback financially isn't enough to support a life much more than getting by (unless you have a lot of students and are well known, or can make it to the top few in your country or the top 20 or so in the world). It's not worth it for that small chance of being successful chess player.
Thus my focus has to be on my work because that is what pays, and the time that is left gets divided up. Now if someone wants to pay my day rate for me to study chess and become titled I'm all ears ;)