There's always Google.
My Chromebook has acquired such apps. It had Google Hangouts and Skype already, it has now got Teams for work and Zoom for some voluntary activities. Telegram has gone on for some secure stuff.
I think the big problem is that there are now so many of them. I used to have several IM apps and an application called Pigin on my PC that pulled them all together. We need something similar for video chats.