I have read quite a bit about analysis of earlier vs later suttas. Unfortunately we cannot know totally for sure what Buddha as historic person has actually said. We don't even know what dialects and when He spoke them.
Often there are unproven assumptions such as:
Buddha did or didn't teach complex philosophy, so very abstract suttas are earlier/later.
Linguistic analysis where earlier Pali words and grammatical forms imply that they are earlier, vs texts with later pali grammar.
The problem is that grammatical analysis can work when the sutta is sufficiently big and varied. If sutta is short and uses limited set of words, then we cannot judge. Also we do not know if the Buddha talked in later form of pali or earlier. He could also have used more archaic forms of pali. Later texts could also use more archaic forms of pali. Large texts could have material from different time periods.
We also have no voice recording of Buddha as historical person. We just have written texts that were first written centuries after the Buddha.
So I guess we need to get the message (let go of craving!) and develop wisdom as much as possible.
"Life is a struggle. Life will throw curveballs at you, it will humble you, it will attempt to break you down. And just when you think things are starting to look up, life will smack you back down with ruthless indifference..."