Delayed response, but there’s a few that I’m aware of that may roughly fit this interest.
Same idea but different instance:
!buyitforlife@sh.itjust.works
Lastly there’s !recommendations@lemmy.world, but this is more for seeking product recommendations rather than providing reviews of products. However currently there’s nothing in their rules prohibiting product review posts, so you could always DM the mod to see if they’re open to them.
Edited & crossed out first couple communities as I reviewed the original thread and saw they weren’t what you were after. I also see that you’ve made a community tailored to what you were looking for via !product_reviews@slrpnk.net, which is apt. Best of luck with it!
In some respects it was somewhat easier to get them to be on multiple platforms instead of moving. Think of the original messenger proliferation, where sometimes people would be on IRC, XMPP, AIM, ICQ, MSN Messenger, or etc. so much so that you had software like Pidgin and Trillian to help consolidate server/chat rooms and friends lists to more easily chat with all your contacts.
Even with Ventrilo, I remember being open to also switching to Mumble or vice versa if there was some hiccup with either.