I think I'm going to counter some of your points. First off, almost none of the people you list would be considered blue collar, that is to say low-skilled working class under someone else's employ. These people were all elites and almost all of whom ran creative studios where they delegated work to uncredited studio artisans.

Secondly, neuroticism is a big problem with creatives and its not like these people didn't have the exact same motivation and mental block issues, its just they found their own ways around them. Drugs and alcohol were often the answer for many of them.

Thirdly, a lot of them led pretty hedonistic lives. Especially your painters. They led Parisian-style cosmopolitan lives of late nights, affairs, hiding gay affairs from the authorities, dealing with hangovers, not showing up for work on days they felt uninspired. Nearly all of these people were self-employed and sold directly to buyers or were funded by patrons. They didn't have any idea of the 9-5 grind and would probably consider it horrifying. Remember, almost everyone on your list lived in pre-capitalist societies and as such had different economic freedoms and systems than ours, and ones that, for successful creatives, meant that actual "work" was entirely different than what you may think it meant.

Art studios for many of these people were a bit like a corporate setup. They'd dictate an outline and leave reference work and a young apprentice or skilled artisan would do a lot of the painting. The master would show up occasionally to correct them and contribute stylistic tones and outlines. The master's real job, like a CEO, was marketing and he was off wining and dining with society to keep his avante grade status as an elite who is welcome in elite circles. These people's social lives were like Versailles's court. They had a great deal of dealmaking and alliance making to even be seen as a viable and important artist. This business and social skill is as important as the art.

And yes high performers were incredible perfectionists. There's no shortage of stories of a famous artist having violent fits because the work didn't match their vision. Mental healthcare back then was poor and Van Gogh obvious was into self harm for example. Perfectionism is the price of entry, imo. It makes us strive for excellence but weighs us down as well. If you're not perfectionist motivated, you may not be able to compete against those who are.

Yes you can cherry pick the prodigious, but they also have artistic block periods, slow work days, etc. And a lot of the higher content creation came after fame when they could afford to farm it out to the factory studio.

So yes, try hard and get over your fears, but there's no magical state of being a "do-er" that fixes everything. Like everything in life moderation is best and a lot of these guys had pretty pleasant lives compared to the stressed out office worker of today. When was the last time you got drunk or had sex at lunch or decided to take a few weeks off to go to Vienna because you were bored with life? Or you decided to move to another kingdom because a low-level regal wants to farm you out to her friends.

tldr; the modern grind is historically inaccurate if you apply it to the past masters. Leisure lifestyles were far more the norm for creatives back then than grindy ones. The nosleep, work 3 jobs, prance on social, never be "off," live with puritan middle class morals, stimulant driven grind is an artifact of our unregulated capitalism, not history.