kable_styling overrides linesep = "" and adds space every 5 rows

This is partially related to this post, but for some reason I seem not to be able to fix my issue. In Quarto, when I create a table using kable with booktabs = TRUE and linesep = "" I get the expected results (no extra space every 5 rows):

---
title: "Test"
format: pdf
---

```{r}
library(kableExtra)
dat <- data.frame(v1 = letters[1:10], v2 = 1:10)
kable(dat, booktabs = TRUE, linesep = "")
```

If I use kable_styling() to get a striped table, an extra space is added after the fifth row:

---
title: "Test"
format: pdf
---

```{r}
library(kableExtra)
dat <- data.frame(v1 = letters[1:10], v2 = 1:10)
kable(dat, booktable = TRUE, linesep = "") |> 
  kable_styling(latex_options = "striped")
```

I get the extra space when I use kable_styling() even without booktabs = TRUE:

---
title: "Test"
format: pdf
---

```{r}
library(kableExtra)
dat <- data.frame(v1 = letters[1:10], v2 = 1:10)
kable(dat) |> 
  kable_styling()
```

To my understanding this is not the expected behavior of kable_styling(), is there something I am missing?

You are not missing something, the table source code generation works differently here and ignores the provided linesep argument (it's more or less a kableExtra topic, see below for an explanation of the issue).

However, you could include a \setlength{\defaultaddspace}{0pt} in the header, this makes the spaces go away (see the booktabs documentation for more details on what it does).

---
title: "Test"
format: 
  pdf:
    include-in-header:
      text: |
        \setlength{\defaultaddspace}{0pt}
---

```{r}
library(kableExtra)
dat <- data.frame(v1 = letters[1:10], v2 = 1:10)
kable(dat) |> 
  kable_styling()
```

Issue explanation

In kable(dat) |> kable_styling() no format argument gets passed. In that case, knitr:::kable_format() defaults to format = "pipe".

This does not result in larger effects in knitr::kable() because within this function knitr:::kable_format_latex() changes format to "latex" because is_latex_output() evaluates to TRUE.

However, in kableExtra::kableStyling() the function kableExtra:::md_table_parser() gets invoked and this function passes no linesep argument to kbl():

return(kbl(table_matrix, col.names=header_row, align=alignment,
            caption=table_caption, booktabs = TRUE,
            longtable = TRUE))

such that the default gets used (what is also discussed in this answer):

linesep = if (booktabs) c('', '', '', '', '\\addlinespace') else '\\hline'