Yup, my wife and kids use it with their Gmail accounts, I use it with my MS account on my Android phone. You can also use the same accounts on desktop clients and Apple devices, so it's not tied to a phone number. However, I'm not sure I would recommend setting it up for twin boys with ADHD (again). 😆
I'm a big fan of Microsoft Teams; full featured chat with easy voice and video calls, and you can sign up with any e-mail address (even non-Microsoft accounts).