So when it comes to team collaboration, we use skype. It works for us, and allows for voice and text chat. Even tho it is old.
I joined a team back in 2016, and they were transitioning from skype to discord. They were also using google hang out
I had issues with discord, and still do.
I was considering skype for business but that is being phased out for Microsoft teams.
I’ve used the Free slack some years ago, and I use paid slack for work.