looks like a "sola scriptura" demonstration by Christ.
It does not say "you foolish men and slow of heart to make me correct you" -- Jesus places the blame on them and not on his own failure to correct them earlier. He speaks to them as being responsible for not reading scripture correctly.
They are indeed responsible. Any failure to grow in prophecy is the fault of believers and results in an inability to properly understand Scripture.
Funny how you ignore the verses that refute Sola Scriptura as the only final autority. Verses supporting authoritative voice:
...Paul relied on authoritative voices and visions. Acts 13:2; Acts 16:6-10; Acts 18:9-11; Acts 22:6-10; Acts 22:17; Acts 22:21; Acts 23:11; 2 Cor 12:9.
...Acts 12:8. Peter hearkened to the voice of an angel.
...Mat 2: Here are found four separate authoritative dreams.
...Post 251. Shows David relying on an authoritative voice time and again.
Solving the Problem of false doctrine
...Luke 4:1 shows Jesus led by the Spirit into the wilderness. That's an authoritive voice. In some places Jesus cited Scripture but He knew more than the text, via the Father's Voice.
...Jesus promised an authoritative voice to His discples (John 16:12-13).
...Both the major and minor prophets made predictions untestable exegetically.
...The prophets knew the secrets of men's hearts not found in Scripture (Acts 5:3-5; Acts 13:9-11; 1 Cor 14:24-25).
...I can't seem to find examples of the prophets testing the Voice exegetically. But we do have Peter relying on an authoritative vision
contradictory to his understanding of Scripture (Acts 10).
...I asked you on what authority you accept Scripture. Burning bosom? You seem to have ignored the question.
...Post 302. I asked you a pertinent question and you seem to have ignored it.
Solving the Problem of false doctrine
...Post 151. The alleged contradiction remains unresolved.
Summary: If God wanted us to believe in Sola Scriptura, He did a very poor job of conveying it. Scripture is prolific with authoritative voices.