“The Doctor and Amy take Vincent Van Gogh - who struggled to sell a single painting in his own lifetime - to a Paris art Gallery in the year 2010”

https://youtu.be/ubTJI_UphPk

I remember the emotional impact of that scene hit me hard when I first saw it. It still hits 89% as hard now upon many repeat viewings.

Another example is Stieg Larsson, author of the Girl with the dragon tattoo triology. He died before these books were published.

Also John Kennedy Toole, his novel The Confederacy of Dunces was published by his mother after his suicide and it ended up winning the Pulitzer.

At least in one of the Van Gogh movies, he says something like 'one day, people will understand'. To me, that suggests that he knew the value of his work whereas OP suggests that Nick Drake didn't know that he created something that people will value.

An example from South Africa: https://en.wikipedia.org/wiki/Searching_for_Sugar_Man