My potential Ph.D. supervisor's research group is very small. Most students are of Masters's level. There are two Ph.D. students, but they are at the end of their Ph.D.; probably, they will be done by the end of this year. Therefore, I will be the only Ph.D. student working with him (starting from October 2022).
He and I have a great relationship. He absolutely adores me, and I also love his personality. He is friendly, easy-going, and doesn't have any ego issues. I can ask him any question via text messenger, and he responds to all of my queries. He doesn't mind even if I ask the same question again.
The only issue that is bugging me is, that his research group has a low rate of publication. I talked to two of his existing Ph.D. students and they told me that one published 8 and the other published 5 papers during their entire Ph.D. To put things in perspective, one of my classmates is doing a Ph.D. at a Canadian university. He has published 15 papers.
So, my question is, how can I cope with this issue and increase the number of publications while doing my Ph.D.?