All the experts according to you. regeneration as in born from above:
Thayer :
313 anagennáō (from 303 /aná, "up, again," which intensifies 1080 /gennáō, "give birth") – properly, born-again or "born from on high."
313 /anagennáō ("born again, from above") is used twice in the NT (1 Pet 1:3,23) – both times referring to God regenerating a believer (giving a supernatural, new birth).
Strongs:
anagennaō an-ag-en-nah'-o From G303 and G1080; to beget or (by extension) bear (again): - beget, (bear) X again.
Begat us again (anagennēsas hēmās). First aorist active articular (ho, who) participle of anagennaō, late, and rare word to beget again, in Aleph for Sirach (Prol. 20), in Philo, in Hermetic writings, in N.T. only here and 1Pe_1:23. “It was probably borrowed by the New Paganism from Christianity” (Bigg). The Stoics used anagennēsis for palingenesia (Tit_3:5). If anōthen in Joh_3:3 be taken to mean “again,” the same idea of regeneration is there, and if “from above” it is the new birth, anyhow.
Vines:
Hath begotten us again (ἀναγεννήσας ἡμᾶς) The verb is used by Peter only, and by him only here and 1Pe_1:23. It is in the aorist tense, and should be rendered, as Rev., begat; because regeneration is regarded as a definite historical act accomplished once for all, or possibly because Peter regards the historical act of Christ's resurrection as virtually effecting the regeneration. The latter sentiment would be Pauline, since Paul is wont to speak of Christians as dying and rising with Christ. Rom_7:4; Rom_6:8-11.
Are you deliberately not reading what you post?
Both Thayer and strong say that is is a regeneration, not a true birth, as your post indicates.
That is exactly in agreement with the Mikva, sometimes mistranslated baptism, but really a washing to bring renewal. This fully fits in with Peter’s message.
Yeshua’s comments, on the other hand, were in explanation of our actual escape from the physical universe, into the realm of the Father, an actual recreation into a different kind of body, an individual creative event for each of us, dead or alive, at the resurrection.
Yeshua was speaking to a high priest, who was in need of no explanation of the gospel of the kingdom, as he had been educated in it throughout his entire life, while Peter was evangelizing to many who had never learned such things, and needed to know how begin their life in Yeshua.
A plain Apples and Oranges situation.