Async rendering order in R shiny

I am trying to figure out async R shiny and there is something fundamental I do not understand.

See my code

library(shiny)
library(future)
library(promises)
library(dplyr)
plan(multiprocess)

ui = shinyUI(fluidPage(
  sidebarLayout(
    sidebarPanel(),
    mainPanel(
      tableOutput("table"),
      tableOutput("table2")
    )
  )
))


server = shinyServer(function(input, output) {

  filtered_df <- reactive({
    future({
      Sys.sleep(10)
      read.csv("https://rstudio.github.io/promises/data.csv") 
    }) %...>%
      filter(state == "NY") %...>%
      arrange(median_income)
  })

  output$table <- renderTable({
    filtered_df()
  })

  output$table2 <- renderTable({
    head(mtcars)
  })

})

shinyApp(ui, server)

I run a Sys.sleep(10) to stall the process. In the meanwhile I want to render a second table under the first.

But somehow nothing is being loaded on my screen until the filtered_df is computed. I am expecting the async code to switch to the next rendering while it is computing the values for the first table.

Why is it now the case? How can I correct this?