What is the degree of authenticity of the hadiths: "Indeed, Allah hastens the taking of the best among you" and "Beware of youth, for it is a fire that flares up and water that ceases"?

The two aforementioned hadiths were not found to be authentically reported in the books of Sunnah. However, some narrations from certain Tabi'un (successors) were found that align with the meaning of the first hadith, such as the saying of Al-Hasan: "Hurry, hurry! What are you lingering for? Your best ones have swiftly departed, and your Prophet has gone, and every day you become more debased."