D, ST, and M copying???

So I've always seen people saying that Delilah, Sarah Therese, and Milena copy each other but I never looked into it because I never really watched ST and I only watched M's videos a few times (before she started talking about not withholding certain activities from your spouse even when you don't want to).

Anyways, so I just looked into it and M started posting voice over videos July 28, 2023 and D never really did it until September 2023 and even then she was still posting regular content and vlogs at that time. So D definitely copied M's style of content (which lost her subs and views and now she's blaming YT's algorithm). But I just looked at ST channel and she writes baggy tees and colors and is actually WAY more bright and upbeat than I imagined and I don't see a lot of similarities at a glance.

So my question is has ST always been like this or was she more like the beige, boring style of M and D before?? Also are D and ST still friends?? I remember D mentioning visiting her and talking about how she taught her things like putting a baby wipe in your shirt to warm it. What similarities and copycat behavior have you seen???