I legitimately think you have no memory of what it used to be like to get on the Internet. "Average internet users" went through all of that. They learned the incantations, and they performed them on a daily basis, to get at something new.
There are people who do not know how to read any written language, at all, who use Smartphones on a daily basis. They learn how to navigate the icons, without any ability to read.
I think you have no memory of what it used to be like to put an app on your iPhone. Over-The-Air installs and updates didn't happen at first. People had to use iTunes on a Desktop, with a cord plugged in, to do stuff.
My 90 year old grandmother knew how to get into the App Store, install apps, and set up accounts.
I think you're vastly underestimating the number of steps users will go through to get at something good.
So, please, think about that for a moment.
But more importantly, if I send you an invite to the same Mastodon server I'm on, you literally skip the one and only one new step ("pick a server") that you've spent all of this time and energy complaining about.
Yup.
The thing you've been bemoaning this entire time isn't even an issue, if you get an invite link.
And frankly, that's probably how the majority of eventual Mastodon users will actually get there - by following a link a friend sends them.
Have a great weekend.