Jer. 32: 39-41 is specifically talking about the Jewish nation after they were scattered with the Babylon overthrow.
Did individual Jews "turn away from God" after they returned from Babylon?
The nation as a whole did have some Jews remaining believer up to the time of Christ.
I would also use Jer. 18 which would apply:
And if at another time I announce that a nation or kingdom is to be built up and planted, 10 and if it does evil in my sight and does not obey me, then I will reconsider the good I had intended to do for it.
OK lets explore this thesis.
First of all what was spoken of by Jeremiah was an Everlasting Covenant to come in which the Holy Spirit would indwell individual believers. Further their salvation would be sealed in righteousness by the fear of Him.
It is a big call to suggest that this was fulfilled by God for the Jews in OT time.
There is no mention anywhere in Scripture of this being the case, Paul is silent on this, Jesus is silent on this.
One telling indication of this not being so, was the sign given to John the Baptist regarding how he was to recognise Messiah.
Messiah was to be the One on whom the Holy Spirit would rest
and remain upon.
This permanent and remaining presence of the Holy Spirit was, until Jesus, not seen among the Jews.
Jesus indicated that the Holy Spirit would not be available to come with such power and fullness until pentecost, and He did not breathe on them to receive the permanent indwelling presence of the Holy Spirit until after the resurrection.
So we have no evidence of such a significant event taking place before Jesus came and died as the sacrificial Lamb, ending the Old covenant period.
The Old Covenant was not fulfilled and replaced until Jesus came to satisfy its requirements.
Then God himself rent the veil from top to bottom, desecrating His temple and removing the authority given to the OT priesthood.
This was done to mark the end of the promise of His presence with His people by means of temple worship because at that point He fulfilled His promise to permanently indwell His chosen under the New Covenant.
There are a multitude of Scriptures to support this signficant new beginning in the relationship between God and Man.
Never before was this Promise through Jeremiah fulfilled, This is the good news of the Gospel - God in Us...