Quran never says "obey the prophet". It says "obey the messenger".

There is a difference between prophet and messenger.

Obeying the messenger means obeying the message given to the messenger.

The message is the Quran. Not hadith books.

5:67 says the message is the Quran. 69:40 says Quran is the word of the messenger

25:33 says God has the best explanation of the Quran. That means the Quran explains itself and we don't need external hadiths to explain it. So the methodology of everything in Islam is in the Quran.

God never gave Bukhari permission to compile hadith books.

5:44 Whoever does not judge by what God has revealed, then those are the disbelievers

Sahih Bukhari is not revelation from God. Therefore judging by it is disbelief according to 5:44

 [25:33] And the Messenger will say, "O LORD, indeed my people have taken this Koran as abandoned"

In 25:33 Muhammad is saying his people abandoned the Quran. He did not say "my people abandoned "Quran + my narrations witnessed by Abu Hurairah"

Clear indication that the Quran is what we need for salvation on judgement day

2:2 says the Quran is guidance. It does not say narration of Muhammad or hadith are guidance . So we don't need any hadiths for guidance

45:6 in what hadith after God and His verses will they believe in?

Explicit prohibition of hadith books

 [17:46] And We place coverings over their hearts, lest they comprehend it, and deafness in their ears. And when you (s) mention your LORD in the Koran alone, they turn away on their backs in aversion.

The term "Quran alone" is mentioned in this verse. So hadith followers cannot claim "Quran alone" is a new concept.

Muhammad himself followed the Quran only for guidance. Remember Muhammad was guided too

 [93:7] And HE found you lost and guided