This is an apples to oranges comparison.

Every TLD is operated by a registry that has a monopoly over that TLD. .dev's registry is Google. .com and .net's registry is Verisign.

GoDaddy is a registrar which resells domains from the registries. You can register .dev domains on GoDaddy just like you can register .com and .net domains.

The bulk of the registration fee goes to the registry. What keeps .com and .net prices reasonable is not that there's no monopoly - Verisign totally has a monopoly - but that Verisign's registry agreement with ICANN forbids this kind of pricing shenanigans whereas Google's registry agreement for .dev doesn't. But I'm sure that when Verisign's registry agreement is up for renewal they will try to renegotiate this.

Yes, someone has to run the official registry, so there's a choke point, unless there are rules in place to prevent abuse. For Verisign's management of .com there's a contract that limits their power. For the new vanity domains there often isn't, so I'm afraid that we will see a lot of this: a cheap price to register a domain, and then a whopping price increase to keep it.

> GoDaddy doesn't have a monopoly on .com, .biz...

GoDaddy is the registry for .biz[0].

That is, GoDaddy was started as a registrar, but the company integrated vertically with a registry division, so it plays both roles now. This was approved by ICANN.

[0] https://en.m.wikipedia.org/wiki/.biz