Yes, I read your post. Paul is paraphrasing OT scriptures. Here are some amongst others...
Deuteronomy 29:4,
Jeremiah 5:21,
Ezekiel 12:2.
They speak of Israels 'stiff-necked' attitudes and an unwillingness to take counsel. The onus is on the people not God yet the OT writers put it onto God because they believe God was responsible for everything that happened, both good and bad.
Paul is using their language to make his point. The point he is not making is that God is responsible for the peoples stiff-neckedness, blind eyes and deaf ears.
You should not twist scripture like this in order to get it to say what you want it to say. What you're saying about the OT writers is absolutely ridiculous. Do you not know that they were inspired by God? Why would God lead them to write something that wasn't true about Him? That's total nonsense.
As I said, it specifically says that God blinded them, but it wasn't permanent and was done for a specific reason which was to allow the gospel of salvation to come to the Gentiles so that, in turn, they would provoke those blinded Israelites to jealousy so that they too would want to be saved. And Paul said he hoped to lead some of those blinded Israelites to salvation (Romans 11:14) and I'm sure he was successful.
I am NOT saying that God is ever solely responsible for anyone's stiff-neckedness, blind eyes and deaf ears. No, not at all. He hardened or blinded people who had already hardened and blinded themselves, but He just increased their blindness, so to speak. Similar to how He hardened Pharaoh's heart for a certain purpose even though Pharaoh had hardened his own heart originally.