In addition to the Chrome app, there is the Chrome extension. They basically do the same thing and the extension has no expiration message. The main reason I wasn't using the extension before is that it didn't provide a desktop icon in Linux. There is a way to fix that by creating a .desktop file[1]. I'm don't remember if there is a similar problem and/or fix on Windows/Mac.
For what it's worth, I've found Hangouts to be the better consumer communications tools. I use other software like Signal and Whatsapp but Hangouts works better between devices. It also makes moving to a voice/video call easy for my less-technically-inclined family members. This is especially true when you want to have a call with multiple users, want to switch for your phone to your computer or want to start a screen share. All of these things can be very useful, even with family members.
Of course, there are trade-offs. There isn't E2E encryption. The video takes a lot of battery on many devices. You never know what's going to happen to the service in the future. What you discuss is being recorded and probably used to target ads.
[1] https://askubuntu.com/questions/771408/separate-icons-for-ch...