sv@0.6.21 not generating a tailwind.config.js file - problem with UI libraries

I created my Svelte project using sv@0.6.21

npx sv@0.6.21 create app

Added the TailwindCSS package

npx sv@0.6.21 add tailwindcss

And then tried to install shadcn-svelte

npx shadcn-svelte@next init

However couldn't because there was no tailwind.config.js file.

I tried to run the init process for TailwindCSS to get a tailwind.config.js and it didn't work. I tried to create a config file manually and it didn't work either.

However creating a project with sv@0.6.18 and adding -initializing flag the TailwindCSS package solved the problem. I am curious why is that?