[SpaghettiCthulu]

The sign-up process doesn't actually begin until you pick an instance and go to it directly, just like with email. It's like complaining about a website that explains what email is and gives you a list of service providers to choose from.

The email service of your choice is the "server" you've chosen. If you go directly to a mastodon instance (the "server") the sign-up process won't require you to choose a server.

[standardUser]

Right, and like I say below, there are very rational and coherent explanations for how Mastodon works, but those explanations mean nothing to the average user, many of whom will not complete sign up because it is so radically different than what they are accustomed to 99.9% of the time when signing up for a new website they heard about (like Twitter for example).