To do anything better, one needs practice. To improve drawing, draw more. To become a better pianist, spend more time at the piano. To become a better cook, cook more. To get stronger or fitter, exercise more.
But there are only so many hours in a day.
One school of thought says, “focus”. Pick a priority and spend more time on that. This is how one goes from amateur to pro. From very good to exceptional. From a jack-of-all-trades to a specialist.
A little bit of each, each day, probably won’t make me exceptional at any one thing. But there can be enrichment in diversity. It’s just a different kind of improvement.
Yes, perhaps to ‘run a business as an illustrator’, one probably needs to be exceptional. The same probably goes for being a professional athlete, chef, or concert pianist. But by definition, most of us are not exceptional and have ‘regular’ jobs with rich & diverse interests, hobbies, and lives.
Neither path is ‘better’ than the other, the more important thing is to recognise and understand the choices we make and why. Only then do we avoid regret.