`inlineStyleThreshold: Infinity` still copies unused css files

Describe the bug

For my understanding, when using inlineStyleThreshold: Infinity, there should be no CSS files produced in the build. But there are CSS files in _app/immutable/assets/ that are not used (because styles are inlined).

Reproduction

Create a new SvelteKit project, add inlineStyleThreshold: Infinity to the svelte config, write some css and build the project

Logs

(As example a simple web server with python, no css file is loaded)
$ python3 -m http.server
Serving HTTP on 0.0.0.0 port 8000 (http://0.0.0.0:8000/) ...
127.0.0.1 - - [16/Feb/2023 12:06:57] "GET / HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:57] "GET /_app/immutable/start-38bb7938.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:57] "GET /_app/immutable/chunks/index-7ff3c067.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:57] "GET /_app/immutable/chunks/singletons-c020755e.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:57] "GET /_app/immutable/chunks/index-2214c1cf.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/chunks/0-aa1d44d9.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/chunks/1-819452d9.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/chunks/2-daaa1281.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/chunks/_layout-44b0675e.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/components/pages/_layout.svelte-93a480e9.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/components/error.svelte-76d40913.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /_app/immutable/components/pages/_page.svelte-affe9d30.js HTTP/1.1" 200 -
127.0.0.1 - - [16/Feb/2023 12:06:58] "GET /favicon.png HTTP/1.1" 200 -

System Info

System:
    OS: Linux 5.15 Arch Linux
  Binaries:
    Node: 19.6.0 - /usr/bin/node
    Yarn: 1.22.19 - /usr/bin/yarn
    npm: 8.19.2 - /usr/bin/npm
  npmPackages:
    @sveltejs/adapter-static: ^2.0.1 => 2.0.1 
    @sveltejs/kit: ^1.0.0 => 1.7.0 
    svelte: ^3.54.0 => 3.55.1 
    vite: ^4.0.0 => 4.1.1

Severity

annoyance

Additional Information

One one HTML Page, TailwindCSS, Prerender and SSR is enabled

Reproduce the issue in a new SvelteKit project using inlineStyleThreshold: Infinity, CSS, TailwindCSS, prerendering, and SSR. Inspect the generated _app/immutable/assets/ directory and the served page; done means styles are inlined without unused CSS files being copied into the build output.