Categoryorder not working when specifying plot type

When using the category order parameter, no plot is generated if the plot type is specified in the plot_ly call:

p <- plotly::plot_ly(type = 'bar')
colNames <- names(iris)
colNames <- colNames[-which(colNames == 'Species')]

for(trace in colNames){
  p <- p %>% plotly::add_trace(data= iris, x = ~ Species, y = as.formula(paste0("~`", trace, "`")), name = trace)
}

p  %>% layout(xaxis = list(categoryorder='total descending'))

With the following warning, which I don't understand since I'm not combining discrete and non-discrete data in the same axis:

Warning message:
Can't display both discrete & non-discrete data on same axis 

If I specify the type in add_trace instead of the plot, then it works correctly and the warning is gone:

p <- plotly::plot_ly()
colNames <- names(df)
colNames <- colNames[-which(colNames == 'Species')]

for(trace in colNames){
  p <- p %>% plotly::add_trace(type = 'bar', data= iris, x = ~ Species, y = as.formula(paste0("~`", trace, "`")), name = trace)
}

p %>% layout(xaxis = list(categoryorder='total descending'))

Maybe this is the intended behavior? If so, why does specifying the type in the traces works and not in the plot? The warning seems unclear to me.

首先使用 iris 运行提供的 R reproduction，并比较 plot_ly(type = 'bar') 与 add_trace(type = 'bar')。跟踪 plot_ly 和 add_trace 如何传递 type，以及 layout(xaxis = list(categoryorder = 'total descending')) 如何处理生成的 traces。完成的标准是 reproduction 不再发出警告，并且 category 排序始终一致。