Usually there's a couple of options for internet access based on your address, not hundreds of servers.

Yeah one choice for me, the local cable company.

But for mastodon, even if it technically "doesn't matter" nobody stops there. You see things written like "The hardest part of getting started on Mastodon is the first step,"[1]

They talk about chosing a server based on region, language, topics of interest, or which ones your friends use. I've even some mention that your server choice can signal your political leanings.

I don't worry about any of those things when I choose an email provider or ISP.

[1] https://www.pcmag.com/how-to/how-to-pick-a-mastodon-server