We barely understand reverse transcription. A huge portion of our DNA is viral in origin and it's not clear that those viruses were retroviruses.

It seems to me that the human body has the capability to perform reverse transcription without encountering a retrovirus.

https://en.wikipedia.org/wiki/Telomerase_reverse_transcriptase

https://www.ahajournals.org/doi/full/10.1161/atvbaha.117.310552#:~:text=One%20source%20of%20endogenous%20reverse%20transcriptase%20%28eRT%29%20activity,is%20implicated%20in%20the%20regulation%20of%20gene%20expression.

We barely understand reverse transcription. A huge portion of our DNA is viral in origin and it's not clear that those viruses were retroviruses.

It seems to me that the human body has the capability to perform reverse transcription without encountering a retrovirus.

https://en.wikipedia.org/wiki/Telomerase_reverse_transcriptase

https://www.ahajournals.org/doi/full/10.1161/atvbaha.117.310552#:~:text=One%20source%20of%20endogenous%20reverse%20transcriptase%20%28eRT%29%20activity,is%20implicated%20in%20the%20regulation%20of%20gene%20expression.