There are so many assumptions and generalizations in your analysis (too many to individually call out). Was any of this based on any research, informal or formal?

You mentioned an audience of your uncle and his poor eyesight, yet your redesign has tiny text for the call's participants (also most people don't have a profile picture), knowing if audio/video is enabled, and for the "join call" button. You've also left out important information you've deemed unimportant such as the password, pin code, and dial-in info.