References:

• It's turned on by default with tsc --init Make skipLibCheck: true the default in --init microsoft/TypeScript#37808 noEmit and skipLibCheck should be on by default in TS compiler options jaredpalmer/tsdx#529 (comment)
• It's turned on by default in create-react-app Speed up TypeScript projects facebook/create-react-app#5903
• It's turned on by default in Angular CLI fix(@schematics/angular): add skipLibCheck to workspace tsconfig angular/angular-cli#16682 Don't enable skipLibCheck in --strict mode angular/angular-cli#16696

Pros:

• Greatly speeds up TypeScript compilation (not a big issue in Vue CLI because we use fork-ts-checker-webpack-plugin)
• Both TypeScript and Vue minor version updates, though as widely tested as they can go, still have chances to break existing type definitions. Users' projects should not break because of code they can't control.
• As Vue 3 is still in the pre-release stage, the type definitions may still have breaking changes and ecosystem packages shall take some time to catch up. For average users, enabling skipLibCheck brings a better experience.

Cons:

• It skipped type checking of all .d.ts files, including the user-owned ones, which isn't ideal. We should turn on type checking for .d.ts files in the project once TypeScript provides such an option.
• For library authors, it may be a better idea to disable it. Because they need to ensure their library type definitions are up-to-date with their upstream dependencies/peerDependencies. (A reference issue in the React community: Question: should we use allowSyntheticDefaultImports:true or skipLibCheck:true in every React project? facebook/create-react-app#8964)

/cc @cexbrayat

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Underlying tools
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

Other information: