Unity toon shader causing object flickering

Is Unity Toon Shader future proof / Can I use it in my commercial game?

I wrote a tutorial for toon/cel shading (link/source in comments)

Unity Shader Programming: Beginners to Advanced Techniques

Milad Kambari

Easy Shaders

Unity Toon Water Shader Tutorial at Roystan

ゼルダの伝説 ブレス オブ ザ ワイルド風 Toon Shader のチュートリアル - 強火で進め

Making A Stylized Toon Shadering Within Unity