Skype absolutely wrecks my MacBook, not sure if the experience is similar on other laptops but I can't even open a PDF while on a Skype call. It would be impossible for me to give a presentation over Skype with my current setup. The software on its own seems reasonably user friendly but if the resource usage is a common issue I don't see Skype being a viable alternative right now.

I would add google meetings... I think it has the nicest interface and works better than the others cross platform.

Its a pity there is no cross platform communication standard - it looks like it will evolve like messaging with dozens of companies.

We have kids with Chromebooks and older laptops and on meeting with 10+ kids, Hangouts Meet becomes intolerable. Not to mention the lack of control - kids mute the teacher, can speak at any time, there's no raising hands, etc. We have to install a bunch of extensions so that we can have a basic functionality in place like the Nod Chrome extension.

Yeah, there's actually tons of alternatives. Everyone and their cousin has a chat app, and video conferencing is a basic feature.