show/estimate distribution given quantiles from quantile regression forest

Question

I would like to show the distribution of given quartiles from quantile regression forest predictions. I currently use this basic code:

library(datasets)
library(quantregForest)
library(dplyr)
library(ggplot2)

x <- iris %>%
    dplyr::select(
        Petal.Length
    ) %>%
    data.matrix()

y <- iris %>%
    dplyr::select(
        Petal.Width
    ) %>%
    data.matrix()

model <- quantregForest(
    x = x
    , y = y
)

what <- c(
      0
    , 0.1
    , 0.2
    , 0.3
    , 0.4
    , 0.5
    , 0.6
    , 0.7
    , 0.8
    , 0.9
    , 1
)

predictions <- predict(model, data.matrix(iris[1,]), what = what)

df <- as.data.frame(as.table(t(predictions)))
ggplot(df, aes(Freq)) +
    geom_density()

Are there better methods? Thanks!