What's ludicrous about acknowledging the motif in Mark of the messianic secret, which Mark develops by portraying the disciples as blind and dumb for not understanding Jesus's parables or his instructions to keep his identity a secret? That topic goes back to Wrede in 1901.

Or what's ludicrous about acknowledging how Mark includes such extended parables in his gospel, using the blindness of the disciples to symbolize everyone's blindness until they're spiritually reborn?

Are you aware that shaking your head and calling someone a dunce proves nothing? You've argued only by assertion, which is to say you've asserted something without backing it up by even a hint of an argument.

Are you denying that the disciples come off as dunces in the Gospel of Mark? Are you denying that historical criticism of the Bible has recognized that theme for at least a century? See, for example, the articles below which address the disciples' blindness in Mark.

https://www.jstor.org/stable/3264783?seq=1

https://www.americamagazine.org/content/the-word/messianic-secret

https://eccelmira.org/articles/the-spiritually-blind-disciples/