Indeed, you are correct
The Buddha in the discourses indicates that the individuals keep company because they possess the same personal characteristic/nature, i.e. dhaatu. This suggests each individual, including specific famous arahants/monks and willers of evil (paapicchaa), has different dhaatus. So, the teaching seems to advise that one much recognise the different dhaatus of individuals.
It makes sense to me! We all have different personal characteristic/nature. Some are simply unable to be ‘something’, ‘someone’, and cannot come together.
According to Choong Mun-keat in Fundamental teachings of Early Buddhism pp. 142-3, “while the SN discourses always mention the ethical dhaatus in connection with past, future and present time, their SA counterparts do not do so”. (Note: the term for time is addhaana, referring to a long period of time, i.e. a lifetime).
If only the Buddha could have done something about these monks with evil desires and their schismatic evil leader - but I guess he was powerless against them.
No wait, he literally made all the rules on who can stay in the Sangha and who not.
The suttas and especially the Vinaya show how concerned Buddha was not to be perceived in a bad way by the population - but he let evil monks do their thing and ruin the reputation of the Sangha? Even the rule not to dig the earth was introduced because monks didn’t take into account the population around who were devoted to Jains. And supposedly ordaining women reduced the true dhamma to 500 years - but letting evil monks be unhindered was somehow “eh, what to do…”
King Milinda seems to have been similarly puzzled by Devadatta, but Nāgasena set his doubts at rest. The gist of his solution: “If you think Devadatta was a lousy bhikkhu, just consider how much worse he’d have been if he hadn’t become a bhikkhu!”
These are nice passages, especially Mil 5.1.3 is still apologetic though. But I don’t think actually that this is about Devadatta. SN 14.14-29 have content which is not repeated anywhere else, namely that “sentient beings come together and converge because of the same dhatu” and these suttas just bring examples for that, including SN 14.15.
So I don’t even take it as an original sutta which has its own independent content. It uses already existing orthodox views on Devadatta to show how dhatus attract each other, and the other suttas in this specific transmission series use other ‘examples’.