It's a lot of work to stay up late (or early) and dial into a meeting. An agenda published at least a day before makes it worth while. If people can't attend, they can add the info you need from them to the agenda.
This isn't "giving people back the time", this is "annoying people who stayed up late to have this meeting".
Nothing is more grating when you are sitting at home late night and have a cacophony of people for the first 5 minutes talking about what the cafeteria is serving. Sure you can mute, but how would you know when to tune in again?
Look, we all love some breakbeat and drum and base. But not while trying to follow a meeting. This also applies to heavy breathing and sneezing. Or eating.
Anyone who has trouble connecting won't be able to tell you. But often you can already type something in the chat. As a person not in the room it is also daunting to try to interject, so often people leave feedback in the chat instead.
Bumping up fonts, not presenting intrinsic and detailed flowcharts is the idea. Imagine blurry things all over them. Even better: a shared slide deck so people can see it on their own machine.
Digital meeting systems are sophisticated and whilst Teams f.e. can make handwritten notes readable and even "see" through people blocking whiteboards, taking notes in the tool on screen includes everyone.