Artists couldn't apply for this, but were officially selected. The program was stopped in 2010, meaning no new recipients have been selected since. As far as I know, there's been no studies surrounding any measurable increase in artistic quality or artistic output.
It is of course easy to point out how deeply unfair such programs are on multiple levels. Unsurprisingly, many recipients have utilized loopholes in order to receive the grant despite having incomes and wealth well above the threshold.
Edit to clarify: Sweden still grants long-term stipends to various artists, sometimes up to a decade. What's described above is a guaranteed, life-long, basic income.