The space.com report has the link to the paper. I did read the 21 page, arXiv paper at the link provided in the article. I note some comments here from that 21 page report. 'A Statistical Estimation of the Occurrence of Extraterrestrial Intelligence in the Milky Way Galaxy',
https://arxiv.org/abs/2012.07902
My observation. The arXiv paper is 21 pages and very interesting. On page 3, ". Furthermore, three major components have remained largely untouched: 1) the probability of life in a pre-biotic condition, 2) different potential timescales for biological evolution, and 3) the probability of self-annihilation of complex life. The work presented herein will incorporate these important, yet often neglected components, in our galactic model."
The arXiv paper contains 17 references to "abiogenesis" and zero to "water". Other sources I use indicate that water, flowing water for example can disrupt abiogenesis. There are more than 4300 exoplanets confirmed now and abiogenesis at work on these exoplanets is not confirmed or ETIs as the paper references. The paper also contains 3 references to "extinction". In the conclusion portion of the paper, "4. Conclusions...The results of our model yield a range of possible quantities for intelligent life over time. We assert that the intelligent life will always be most abundant approximately 4 kpc from the galactic center, peaking at time around 8 Gyrs, decreasing monotonically from that peak point, and that a majority of potential intelligent life is still young. The exact number of the intelligent life estimated here is not the focus of our work; rather, it is instead the development of a statistical, comprehensive galactic picture tracing the potential growth propensity of intelligent life over a course of ~20 billion years."
The 21 page arXiv paper is intriguing. The civilization on Earth documented is very young by this new model for SETI and ETI searches. Other ETI civilizations are likely very old or extinct. However, showing the ETIs were there or are there today remains a challenge for testing and verification. The space.com article at the end does note "The paper has been submitted to a journal for publication and is awaiting peer review."
Models like this in astrobiology and astronomy can be used to define constraints on UFO visitors coming from the stars to Earth---Rod